KR102391244B1 - Pressurized etching apparatus and controlling method thereof - Google Patents

Abstract

Disclosed are an etching apparatus and a method for controlling the same. The apparatus of the present invention includes: an etching apparatus comprising: a pressure chamber in which one or more wafers are accommodated; a door installed in the pressure chamber to open and close the pressure chamber; a guide unit connected to the door and the pressure chamber unit to guide the movement of the door; a door restraining unit for holding the door in a pressed state to the pressure chamber unit so that the door closes the pressure chamber unit; and an etchant supply unit connected to the pressure chamber unit to supply the etchant solution to the pressure chamber unit in a state in which the door closes the pressure chamber unit.

Description

Etching apparatus and its control method

The present invention relates to an etching apparatus and a method for controlling the same, and more particularly, to an etching apparatus capable of improving etching performance and suppressing evaporation of an etching solution and a control method thereof.

A silicon nitride film is used as a representative insulating film in a semiconductor process. The silicon nitride film has a structure in contact with a silicon oxide film, a polysilicon film, and the surface of a silicon wafer, and is deposited by a chemical vapor deposition (CVD) process, which is removed through dry etching and wet etching.

Dry etching is mainly performed under vacuum by putting a fluorine-based gas and an inert gas, but there is a limit to commercial use because equipment for performing dry etching is expensive.

Accordingly, wet etching using phosphoric acid is widely used rather than dry etching. Specifically, the wet etching is to selectively etch a desired target layer on an object (substrate, etc.) by a chemical reaction of the etchant. According to the required characteristics or etching degree, the etching solution having a composition ratio corresponding thereto is easily mixed to form an operation. It provides improved work compatibility compared to dry etching. In addition, a large number of objects can be processed at once, and the device is inexpensive.

However, in the wet etching, a portion of the etchant is vaporized during the etching process, and the temperature of the object may be lowered by the heat of vaporization, and it is difficult to control the concentration of the etchant due to the vaporization of the etchant, resulting in CD loss. Therefore, in order to keep the concentration of the etchant constant, a large amount of deionized water and etchant are currently introduced into the etchant to etch the object, and in this case, economic loss due to the input of a large amount of deionized water and etchant can be large

The background technology of the present invention is disclosed in Republic of Korea Patent Registration No. 10-0691479 (2007. 03. 12 Announcement: Title of Invention: Large-area substrate etching apparatus).

SUMMARY OF THE INVENTION It is an object of the present invention to provide an etching apparatus capable of improving etching performance and suppressing evaporation of an etching solution, and a method for controlling the same.

An etching apparatus according to the present invention includes: a pressure chamber in which one or more wafers are accommodated; a door installed in the pressure chamber to open and close the pressure chamber; a guide part connected to the door and the pressure chamber part to guide the movement of the door; a door restraining part for maintaining the door in a compressed state in the pressure chamber part so that the door closes the pressure chamber part; and an etchant supply unit connected to the pressure chamber to supply the etchant to the pressure chamber in a state in which the door closes the pressure chamber.

The guide part may be connected to the door to move together with the door, and may be installed on both sides of the pressure chamber part.

a plurality of guide bars connected to both sides of the door and movably installed in the pressure chamber; and a connecting member connected to the plurality of guide bars and constrained to the door restraint unit.

The door restraint portion includes a restraint clamp disposed on a side surface of the pressure chamber; and a clamp driving part connected to the restraining clamp and moving the restraining clamp to restrain the guide part.

The restraining clamps may be respectively disposed on both side surfaces of the pressure chamber.

Two of the clamp driving units may be connected to each of the restraining clamps to restrain both sides of the restraining clamp, respectively.

The door restraint portion includes a restraint clamp disposed on a side surface of the pressure chamber; and a clamp driving unit connected to the restraining clamp and moving the restraining clamp to restrain the door.

The restraining clamps may be respectively disposed on both side surfaces of the pressure chamber.

One clamp driving unit may be connected to each of the restraining clamps.

The etching apparatus may further include a door driving unit installed in the pressure chamber unit to move the door.

The etchant supply unit includes an etchant storage tank in which the etchant is stored; an etchant circulation pipe connected to the etchant storage tank and the pressure chamber to supply the etchant to the inside of the pressure chamber; and a circulation driving unit connected to the etchant circulation pipe unit.

The supply port of the etchant circulation pipe part may be connected to the lower side of the pressure chamber part, and the discharge port of the etchant circulation pipe part may be connected to the upper side of the pressure chamber part.

The pressure chamber part may further include a first diffusion part disposed under the pressure chamber part to diffuse the etchant introduced through the supply port.

The pressure chamber part may further include a second diffusion part disposed above the pressure chamber part to diffuse the etchant discharged from the inside of the pressure chamber part to the discharge port.

A method of controlling an etching apparatus according to the present invention includes: putting a wafer into a pressure chamber; closing the pressure chamber part as the door is moved by the guide part; maintaining the door in a pressed state to the pressure chamber part when the pressure chamber part of the door is closed; and supplying the etchant to the pressure chamber by the etchant supply unit.

In the step of maintaining the door pressed to the pressure chamber part when the pressure chamber part of the door is closed, a restraining clamp of the door restraint part may restrain the guide part.

In the step of maintaining the door pressed to the pressure chamber part when the pressure chamber part of the door is closed, the restraining clamps of the door restraint part may restrain both sides of the door.

In the step of supplying the etchant to the pressure chamber by the etchant supply unit, the etchant may be circulated to the pressure chamber and the etchant storage tank through the visual fluid supply unit.

In the step of supplying the etchant to the pressure chamber by the etchant supply unit, the etchant flowing into the pressure chamber may be diffused while passing through the first diffusion unit.

In the step of supplying the etchant to the pressure chamber by the etchant supply unit, the etchant discharged from the pressure chamber may be diffused while passing through the second diffusion unit.

According to the present invention, since the wafer injected into the pressure chamber is etched in a high-temperature and high-pressure atmosphere, the etching performance of the wafer can be improved.

In addition, according to the present invention, since the high-pressure etchant is supplied to the pressure chamber, evaporation of the etchant in the pressure chamber can be suppressed.

1 is a circuit diagram schematically showing an etching apparatus according to a first embodiment of the present invention.
2 is a side view schematically illustrating an etching apparatus according to a first embodiment of the present invention.
3 is a plan view schematically illustrating an etching apparatus according to a first embodiment of the present invention.
4 is a perspective view schematically illustrating an etching apparatus according to a first embodiment of the present invention.
5 is a plan view schematically illustrating a state in which the door is opened in the etching apparatus according to the first embodiment of the present invention.
6 is a side view schematically illustrating a state in which a wafer is put into a pressure chamber in the etching apparatus according to the first embodiment of the present invention.
7 is a side view schematically illustrating a state in which the door is closed in the etching apparatus according to the first embodiment of the present invention.
8 is a plan view schematically illustrating a state in which the door is closed in the etching apparatus according to the first embodiment of the present invention.
9 is a plan view schematically illustrating a state in which the door restraining unit restrains the connecting member of the guide part in the etching apparatus according to the first embodiment of the present invention.
10 is a flowchart illustrating a control method of an etching apparatus according to a first embodiment of the present invention.
11 is a schematic side view of an etching apparatus according to a second embodiment of the present invention.
12 is a schematic front view of an etching apparatus according to a second embodiment of the present invention.
13 is a plan view schematically illustrating a state in which the door is opened in the etching apparatus according to the second embodiment of the present invention.
14 is a side view schematically illustrating a state in which a wafer is put into a pressure chamber in the etching apparatus according to the second embodiment of the present invention.
15 is a side view schematically illustrating a state in which the door is closed in the etching apparatus according to the second embodiment of the present invention.
16 is a plan view schematically illustrating a state in which the door is closed in the etching apparatus according to the first embodiment of the present invention.
17 is a plan view schematically illustrating a state in which the door restraint unit restrains the connecting member of the guide part in the etching apparatus according to the first embodiment of the present invention.

Hereinafter, embodiments of an etching apparatus and a control method thereof according to the present invention will be described with reference to the accompanying drawings. In the process of explaining the etching apparatus and its control method, the thickness of lines or the size of components shown in the drawings may be exaggerated for clarity and convenience of explanation. In addition, the terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of the user or operator. Therefore, definitions of these terms should be made based on the content throughout this specification.

First, an etching apparatus according to a first embodiment of the present invention will be described.

1 is a circuit diagram schematically showing an etching apparatus according to a first embodiment of the present invention, FIG. 2 is a side view schematically showing an etching apparatus according to a first embodiment of the present invention, and FIG. It is a plan view schematically showing the etching apparatus according to the first embodiment, and FIG. 4 is a perspective view schematically showing the etching apparatus according to the first embodiment of the present invention.

1 to 4 , the etching apparatus 100 according to the first embodiment of the present invention includes a pressure chamber unit 120 , a door 130 , a guide unit 140 , a door restraint unit 150 , and an etchant. A supply unit 170 is included.

One or more wafers W are accommodated in the pressure chamber unit 120 . The pressure chamber part 120 may be formed in the shape of a square box in which an opening is formed on the front side. The wafer W may be automatically inserted into the pressure chamber unit 120 by the carrier 110 or may be manually inserted. When the etching apparatus 100 is applied to a single-wafer type, one wafer W is loaded in the wafer storage box 115 of the carrier 110 . In addition, when the etching apparatus 100 is applied to a batch type, a plurality of wafers W are loaded in the wafer storage box 115 of the carrier 110 in an upright state.

The carrier 110 includes a carrier driving unit 111 and a gripper 113 installed on both sides of the carrier driving unit 111 and constraining the wafer storage box 115 as it is rotated by the carrier driving unit 111 . The gripper 113 may be formed in a plate shape. As the carrier 110 , various forms may be applied as long as the wafer holder 115 is moved.

The pressure chamber part 120 includes an inner chamber part 121 in which the etchant is accommodated, and an outer chamber part 123 installed to surround the outside of the inner chamber part 121 . The etchant is supplied to the pressure chamber 120 at a high temperature of about 150-200° C. and a high pressure of about 5-10 bar.

A pressure chamber 122 is formed inside the inner chamber part 121 . The inner chamber part 121 does not chemically react with the etchant and may be formed of a chemical-resistant and heat-resistant material such as a Teflon material that can withstand high temperatures. Accordingly, an etchant of approximately 150-200° C. may be supplied to the pressure chamber 122 of the pressure chamber unit 120 .

The outer chamber part 123 may be formed of a metallic material such as stainless steel to prevent deformation of the inner chamber part 121 due to the pressure of the etchant. Accordingly, the outer chamber part 123 can prevent the inner chamber part 121 from being deformed by a high pressure of about 5-10 bar.

A vent unit 127 may be connected to the pressure chamber unit 120 to adjust the pressure in the pressure chamber 122 of the pressure chamber unit 120 . When the pressure of the pressure chamber part 120 is increased by more than a preset pressure, the vent part 127 is opened.

The door 130 is installed in the pressure chamber part 120 to open and close the pressure chamber part 120 . The door 130 may be formed in a plate shape to open and close the opening of the pressure chamber unit 120 . A sealing member (not shown) is installed on the inner surface of the door 130 and around the opening of the inner chamber part 121 to prevent the etchant from leaking.

The guide unit 140 is connected to the door 130 and the pressure chamber unit 120 to guide the movement of the door 130 . At this time, the end of the guide part 140 is fixed to the door 130 , and the guide part 140 is movably installed on both sides of the pressure chamber part 120 . The extension plate part 125 is formed to protrude from both sides of the opening of the pressure chamber part so that the guide part 140 is slidably fitted.

The guide unit 140 is connected to the door 130 to move together with the door 130 , and is installed on both sides of the pressure chamber unit 120 . Since the guide unit 140 is installed on both sides of the pressure chamber unit 120 , it is possible to prevent the door 130 from shaking when the door 130 is moved. In addition, when the door 130 closes the pressure chamber unit 120 , the guide unit 140 restrains the door 130 to prevent a gap from being generated between the pressure chamber unit 120 and the door 130 . .

The guide unit 140 is connected to both sides of the door 130 , a plurality of guide bars 141 movably installed in the pressure chamber unit 120 , and a plurality of guide bars 141 are connected to the door restraint. It includes a connecting member 143 constrained to the portion 150 . A plurality of guide bars 141 are installed on both sides of the pressure chamber unit 120 so as to be parallel to the moving direction of the door 130 . The guide bar 141 may be formed in the form of a circular rod or a polygonal rod. The connection members 143 are disposed on both sides of the pressure chamber part 120 , respectively. The connecting member 143 is disposed in parallel in the vertical direction of the pressure chamber unit 120 . On both sides of the connection member 143 in the width direction, the constraining ribs 144 are formed to protrude by being caught and constrained by the door restraining unit 150 . The restraining ribs 144 are formed in parallel along the longitudinal direction of the connecting member 143 . The restraining ribs 144 may be integrally formed in a straight line, or may be formed of a plurality of restraining pieces arranged in a line at regular intervals.

The door restraint unit 150 maintains the door 130 in a pressed state to the pressure chamber unit 120 so that the door 130 maintains the closed state of the pressure chamber unit 120 . Accordingly, the etchant in a high-temperature and high-pressure state may be supplied to the pressure chamber unit 120 to etch the wafer (W). In addition, since the etchant is supplied to the pressure chamber unit 120 in a high pressure state, it is possible to suppress evaporation or volatilization of the etchant by the high pressure.

The door restraint unit 150 includes a restraint clamp 151 and a clamp driving unit 153 . The restraining clamp 151 is disposed on the side surface of the pressure chamber unit 120 . At this time, the restraining clamp 151 is disposed on the opposite side of the door 130 of the pressure chamber unit 120 . The clamp driving unit 153 is connected to the restraining clamp 151 and moves the restraining clamp 151 to restrain the guide unit 140 . The clamp driving unit 153 is disposed on the rear side of the pressure chamber unit 120 .

When the door 130 is moved to close the opening of the pressure chamber part 120 , as the clamp driving part 153 is driven, the restraining clamp 151 restrains the connecting member 143 of the guide part 140 . Therefore, even when the high-temperature and high-pressure etchant is supplied to the pressure chamber 122 of the pressure chamber unit 120 , the door 130 tightly seals the pressure chamber 122 of the pressure chamber unit 120 to prevent leakage of the etchant. can do. In addition, since the high-pressure etchant is supplied to the pressure chamber unit 120 , evaporation of the etchant in the pressure chamber unit 120 may be suppressed. In addition, since the wafer W injected into the pressure chamber 120 is etched in a high-pressure atmosphere, the etching performance of the wafer W may be improved.

The restraining clamp 151 is formed in a “]” shape in which both sides are bent toward the pressure chamber unit 120 . The restraining clamp 151 may be formed in various shapes. As the clamp driving unit 153 , a motor unit for moving the restraining clamp 151 may be applied. The clamp driving unit 153 may be applied in various forms such as a cylinder for restraining the guide unit 140 by moving the restraining clamp 151 , a ball screw type driving unit, and a linear motor unit. When the ball screw type driving unit is applied, the restraining clamp 151 is moved as the ball screw type driving unit is rotated.

The restraining clamps 151 are respectively disposed on both side surfaces of the pressure chamber unit 120 . Accordingly, the restraining clamps 151 may stably restrain both sides of the guide unit 140 so that the door 130 is tightly pressed against the opening of the pressure chamber unit 120 .

Two clamp driving units 153 are connected for each restraining clamp 151 to restrain both sides of the restraining clamp 151, respectively. As the two clamp driving units 153 simultaneously pull both upper and lower sides of the restraining clamp 151 , the guide unit 140 may be restrained.

The etching apparatus 100 further includes a door driving unit 160 installed in the pressure chamber unit 120 to move the door 130 . The door driving unit 160 may have various forms such as a cylinder for moving the door 130 and the guide unit 140 , a ball screw type driving unit, and a linear motor unit. Of course, the etching apparatus 100 may manually open and close the door 130 .

A case in which the linear motor unit is applied to the door restraint unit 150 will be described. The linear motor unit includes a stator 161 formed in parallel in the front-rear direction on the side surface of the pressure chamber unit 120, and a mover 163 that moves the guide unit 140 as it is movably coupled to the stator 161. do. N poles and S poles are alternately arranged in the stator 161 , and N poles and S poles are arranged in the mover 163 . As the N and S poles of the stator 161 and the mover 163 generate attractive and repulsive forces, the mover 163 is moved.

The etchant supply unit 170 is connected to the pressure chamber unit 120 to supply the etchant to the pressure chamber unit 120 in a state in which the door 130 closes the pressure chamber unit 120 . Accordingly, a high-pressure closed loop may be formed so that the high-pressure etchant stored in the etchant supply unit 170 may be supplied to the pressure chamber unit 120 .

The etchant supply unit 170 includes an etchant storage tank 171 , an etchant circulation pipe unit 173 , and a circulation driving unit 177 . Visual fluid is stored in the etchant storage tank 171 . The etchant circulation pipe part 173 is connected to the etchant storage tank 171 and the pressure chamber part 120 to supply the etchant to the inside of the pressure chamber part 120 . The circulation driving unit 177 is connected to the etchant circulation pipe unit 173 . A heating device 172 may be installed in the etchant storage tank 171 to heat the etchant to a high temperature of approximately 150-200°C. As the heating device 172, a heater that generates heat as power is supplied may be applied.

The etchant circulation pipe part 173 is a first circulation pipe part 174 for supplying the etchant of the etchant storage tank 171 to the pressure chamber part 120, and the etchant of the pressure chamber part 120 to the etchant storage tank 171. It includes a second circulation pipe part 175 for supplying. An opening control valve 176 is installed in the first circulation pipe part 174 . As the etchant driving unit 177 , a pump for flowing the etchant to the etchant circulation pipe 173 may be applied.

A pressurizing unit 181 is connected to the etchant storage tank 171 to maintain the internal pressure of the etchant storage tank 171 at a preset pressure, and the pressurizing unit 181 is configured to control the internal temperature of the etchant storage tank 171 . The temperature control unit 182 is connected. The pressurizing unit 181 may supply compressed gas to the etchant storage tank 171 to adjust the internal pressure of the etchant storage tank 171 to about 3-10 bar.

The etchant storage tank 171 is connected to an exhaust unit 183 for discharging the gas inside. As the exhaust unit 183 discharges the gas of the etchant storage tank 171 to the outside, the internal pressure of the etchant storage tank 171 is maintained at a high pressure.

When the etchant driving unit 177 is driven, the etchant of the etchant storage tank 171 is supplied to the inside of the pressure chamber unit 120 through the etchant circulation pipe unit 173, and the etchant of the pressure chamber unit 120 is the etchant circulation pipe unit It is discharged to the etchant storage tank 171 through (173). An etchant replenisher (not shown) may be connected to the etchant storage tank 171 to supplement and replace the etchant. Since the etchant is circulated along the etchant storage tank 171 , the etchant circulation pipe part 173 , the pressure chamber part 120 and the etchant circulation pipe part 173 , the temperature of the etchant supplied to the pressure chamber part 120 is maintained constant. can be In addition, since the etchant flows along the high-pressure closed loop, evaporation and volatilization of the etchant can be prevented.

The supply port 174a of the etchant circulation pipe part 173 is connected to the lower side of the pressure chamber part 120 , and the discharge port 175a of the etchant circulation pipe part 173 is connected to the upper side of the pressure chamber part 120 . The etchant may be supplied to the lower side of the pressure chamber unit 120 and filled in the pressure chamber unit 120 and then discharged to the upper side of the pressure chamber unit 120 . Since the etchant is filled from the lower side of the pressure chamber part 120 , the wafer W may be etched while the etchant is completely filled in the pressure chamber part 120 . Accordingly, since the etchant is evenly in contact with the entire surface of the wafer W, the etching performance of the wafer W may be improved.

The pressure chamber unit 120 further includes a first diffusion unit 191 disposed below the pressure chamber unit 120 to diffuse the etchant introduced through the supply port 174a. The first diffusion unit 191 covers the entire lower surface of the pressure chamber unit 120 . The first diffusion unit 191 may be a first diffusion plate in which a plurality of first diffusion hole portions 191a are formed. Since the etchant of the etchant circulation pipe part 173 is diffused almost uniformly while passing through the first diffusion part 191 , the etchant can be almost uniformly in contact with all the wafers W while flowing between the erected wafers W. Accordingly, the etching performance of the wafer W may be improved.

In addition, in a state in which the pressure chamber unit 120 is sealed by the door 130 , the high-pressure etchant flows between the erected wafers W to etch the wafer W, and the etchant supply unit 170 forms a closed loop. Therefore, it is possible to suppress the evaporation of the etchant even if a high-temperature etchant of about 150-200 ℃ is used.

The pressure chamber unit 120 further includes a second diffusion unit 193 disposed above the pressure chamber unit 120 to diffuse the etchant discharged from the inside of the pressure chamber unit 120 to the discharge port 175a. do. The second diffusion unit 193 covers the entire upper surface of the pressure chamber unit 120 . The second diffusion unit 193 may be a second diffusion plate in which a plurality of second diffusion hole portions 193a are formed. Since the etchant of the pressure chamber part 120 is diffused almost uniformly while passing through the second diffusion part 193 , the discharge rate of the etchant from the entire upper side of the pressure chamber part 120 may be maintained almost uniformly. Accordingly, the etching performance on the upper side of the pressure chamber part 120 may be improved.

A method for controlling the etching apparatus according to the first embodiment of the present invention configured as described above will be described.

5 is a plan view schematically illustrating a state in which a door is opened in the etching apparatus according to the first embodiment of the present invention, and FIG. 6 is a wafer in the pressure chamber in the etching apparatus according to the first embodiment of the present invention. Fig. 7 is a side view schematically showing a state in which the door is closed in the etching apparatus according to the first embodiment of the present invention, and Fig. 8 is the etching according to the first embodiment of the present invention. It is a plan view schematically showing a state in which the door is closed in the apparatus, and FIG. 9 is a plan view schematically showing a state in which the door restraint part restrains the connecting member of the guide part in the etching apparatus according to the first embodiment of the present invention, and FIG. is a flowchart illustrating a method for controlling an etching apparatus according to a first embodiment of the present invention.

5 to 10 , the wafer W is loaded in the wafer holder 115 of the carrier 110 ( S11 ). In this case, one or a plurality of wafers W may be loaded on the carrier 110 . When the etching apparatus 100 is applied to a single-wafer type, one wafer W is loaded in the wafer storage box 115 of the carrier 110 in an upright state. In addition, when the etching apparatus 100 is applied to a batch type, a plurality of wafers W are loaded in the wafer storage box 115 of the carrier 110 in an upright state.

The carrier 110 moves the wafer W to the upper side of the pressure chamber 120 (S12). At this time, the door 130 is moved to the front side to open the opening of the pressure chamber unit 120 , and the carrier 110 is located above the door 130 .

As the carrier 110 moves to the lower side of the door 130 , the wafer W is put into the pressure chamber 120 ( S13 ). At this time, the lower side of the pressure chamber part 120 is moved to the front side together with the door 130 , and the wafer W is seated under the pressure chamber part 120 of the door 130 .

As the gripper 113 of the carrier 110 moves outward, the wafer storage box 115 is separated from the gripper 113 . As the carrier 110 moves upward, the carrier 110 deviates from the pressure chamber part 120 (S14).

As the door 130 is moved by the guide unit 140, the pressure chamber unit 120 is closed (S15). At this time, the guide unit 140 is moved to the rear side of the pressure chamber unit 120 together with the door 130 . In addition, the guide bar 141 is moved while sliding on the extension plate part 125 of the pressure chamber part 120 , and the connecting member 143 is moved to the rear side of the pressure chamber part 120 . When the door 130 completely closes the pressure chamber part 120 , the connecting member 143 of the guide part 140 faces the restraining clamp 151 of the door restraining part 150 . At this time, the connecting member 143 is arranged in parallel with the restraining clamp 151 .

The door restraint unit 150 maintains the door 130 in a compressed state to the pressure chamber unit 120 (S16). At this time, as the clamp driving unit 153 is driven, the restraining clamp 151 is moved to press the connecting member 143 of the guide unit 140 . Since the guide part 140 is restrained by the restraining clamp 151 , the door 130 maintains a state in which it is pressed against the pressure chamber part 120 . Accordingly, the pressure chamber 122 of the pressure chamber part 120 is sealed by the door 130 .

The etchant supply unit 170 supplies the etchant to the pressure chamber unit 120 (S17). The etchant is circulated to the pressure chamber 120 and the etchant storage tank 171 through the visual fluid supply unit 170 . At this time, the etchant in the etchant storage tank 171 is supplied to the pressure chamber unit 120 through the first circulation pipe unit 174 , and the etchant in the pressure chamber unit 120 is stored as the etchant through the second circulation pipe unit 175 . discharged to the tank 171 .

As the visual fluid circulates along the etchant supply unit 170, the wafer W is etched (S18). At this time, the etchant flowing into the pressure chamber unit 120 is diffused while passing through the first diffusion unit (191). Since the etchant of the etchant circulation pipe unit 173 is almost uniformly diffused while passing through the first diffusion unit 191, the etchant flows between all the wafers W and is almost uniformly supplied to and in contact with all the wafers W. . Accordingly, the etching performance of the wafer W may be improved.

In addition, the etchant discharged from the pressure chamber unit 120 is diffused while passing through the second diffusion unit (193). Since the etchant of the pressure chamber part 120 is diffused almost uniformly while passing through the second diffusion part 193 , the discharge rate of the etchant from the entire upper side of the pressure chamber part 120 may be maintained almost uniformly. In addition, since the high-temperature etchant of 150-200° C. is diffused while passing through the second diffusion unit 193 in a high-pressure environment of 3-10 bar, evaporation of the etchant can be suppressed as the high-temperature etchant is compressed by the high-pressure environment. Accordingly, the etching performance on the upper side of the pressure chamber part 120 may be improved.

Next, an etching apparatus according to a second embodiment of the present invention will be described. Since the second embodiment is substantially the same as that of the first embodiment except for the door restraint portion of the first embodiment, the same reference numerals are given to the same components and the description thereof will be omitted.

11 is a side view schematically showing an etching apparatus according to a second embodiment of the present invention, FIG. 12 is a front view schematically showing an etching apparatus according to a second embodiment of the present invention, and FIG. It is a plan view schematically showing a state in which the door is opened in the etching apparatus according to the second embodiment.

11 to 13 , the door restraint unit 150 includes a restraining clamp 151 and a clamp driving unit 153 .

The restraining clamp 151 is disposed on the side surface of the pressure chamber unit 120 . The restraining clamp 151 is disposed on the front side of the pressure chamber part. The clamp driving unit 153 is connected to the restraining clamp 151 and moves the restraining clamp 151 to restrain the door 130 . The clamp driving unit 153 is disposed on the front side of the pressure chamber unit. Constraint ribs 152 may be formed on both sides of the restraining clamp 151 in the width direction to restrain the door 130 and the extension plate part 125 . When the door 130 is moved to close the opening of the pressure chamber part 120 , the door 130 and the extension plate part 125 are disposed between the restraining ribs 152 of the restraining clamp 151 as the clamp driving part 153 is driven. ) is inserted and bound. Accordingly, the door 130 may be tightly pressed against the opening of the pressure chamber unit 120 .

The restraining clamps 151 are formed in the form of long and thin panels on both sides of the pressure chamber part 120 . The restraining clamp 151 may be formed in various shapes. As the clamp driving unit 153 , various types such as a cylinder, a ball screw type driving unit, and a linear motor unit may be applied.

The restraining clamps 151 are respectively disposed on both side surfaces of the pressure chamber unit 120 . Accordingly, the restraining clamps 151 may stably restrain both sides of the door 130 so that the door 130 is tightly pressed against the opening of the pressure chamber part 120 . In addition, since the restraining clamp 151 presses both sides of the door 130 , even if the door 130 is slightly twisted, the correct position can be corrected by the pressing force of the restraining clamp 151 . Accordingly, it is possible to prevent the etchant from leaking between the door 130 and the opening of the pressure chamber unit 120 .

One clamp driving unit 153 is connected to each restraining clamp 151 to restrain the restraining clamp 151 . At this time, the clamp driving unit 153 is connected to the longitudinal center of the restraining clamp 151 . As one clamp driving unit 153 pulls the central portion of the restraining clamp 151 , the door 130 may be restrained. Accordingly, in the second embodiment, the number of parts of the clamp driving unit 153 can be reduced.

A method for controlling the etching apparatus according to the second embodiment of the present invention configured as described above will be described.

11 is a side view schematically showing an etching apparatus according to a second embodiment of the present invention, FIG. 12 is a front view schematically showing an etching apparatus according to a second embodiment of the present invention, and FIG. It is a plan view schematically illustrating a state in which the door is opened in the etching apparatus according to the second embodiment, and FIG. 14 schematically shows a state in which the wafer is put into the pressure chamber in the etching apparatus according to the second embodiment of the present invention. 15 is a side view schematically illustrating a state in which the door is closed in the etching apparatus according to the second embodiment of the present invention, and FIG. 16 is a state in which the door is closed in the etching apparatus according to the first embodiment of the present invention. is a plan view schematically illustrating a , and FIG. 17 is a plan view schematically illustrating a state in which the door restraint unit restrains the connecting member of the guide part in the etching apparatus according to the first embodiment of the present invention.

10 to 17 , the wafer W is loaded in the wafer holder 115 of the carrier 110 ( S11 ). In this case, one or a plurality of wafers W may be loaded on the carrier 110 . When the etching apparatus 100 is applied to a single-wafer type, one wafer W is loaded in the wafer storage box 115 of the carrier 110 in an upright state. In addition, when the etching apparatus 100 is applied to a batch type, a plurality of wafers W are loaded in the wafer storage box 115 of the carrier 110 in an upright state.

The carrier 110 moves the wafer W to the upper side of the pressure chamber 120 (S12). At this time, the door 130 is moved to the front side to open the opening of the pressure chamber unit 120 , and the carrier 110 is located above the door 130 .

As the carrier 110 moves to the lower side of the door 130 , the wafer W is put into the pressure chamber 120 ( S13 ). At this time, the lower side of the pressure chamber part 120 is moved to the front side together with the door 130 , and the wafer W is seated under the pressure chamber part 120 of the door 130 .

As the gripper 113 of the carrier 110 moves outward, the wafer storage box 115 is separated from the gripper 113 . As the carrier 110 moves upward, the carrier 110 deviates from the pressure chamber part 120 (S14).

As the door 130 is moved by the guide unit 140, the pressure chamber unit 120 is closed (S15). At this time, the guide unit 140 is moved to the rear side of the pressure chamber unit 120 together with the door 130 . In addition, the guide bar 141 is moved while sliding on the extension plate part 125 of the pressure chamber part 120 . When the door 130 completely closes the pressure chamber part 120 , both sides of the door 130 and the extension plate part 125 face the restraining clamp 151 of the door restraining part 150 . In this case, both sides of the door 130 and the extension plate part 125 are arranged in parallel with the restraining clamp 151 .

The door restraint unit 150 maintains the door 130 in a compressed state to the pressure chamber unit 120 (S16). At this time, as the clamp driving unit 153 is driven, the restraining clamp 151 is moved to press both sides of the door 130 and the extension plate unit 125 . Since both sides of the door 130 and the extension plate part 125 are restrained by the restraining clamp 151 , the door 130 maintains a state in which it is pressed against the pressure chamber part 120 . Accordingly, the pressure chamber 122 of the pressure chamber part 120 is sealed by the door 130 .

The etchant supply unit 170 supplies the etchant to the pressure chamber unit 120 (S17). The etchant is circulated to the pressure chamber 120 and the etchant storage tank 171 through the visual fluid supply unit 170 . At this time, the etchant in the etchant storage tank 171 is supplied to the pressure chamber unit 120 through the first circulation pipe unit 174 , and the etchant in the pressure chamber unit 120 is stored as the etchant through the second circulation pipe unit 175 . discharged to the tank 171 .

As the visual fluid circulates along the etchant supply unit 170, the wafer W is etched (S18). At this time, the etchant flowing into the pressure chamber unit 120 is diffused while passing through the first diffusion unit (191). Since the etchant of the etchant circulation pipe part 173 is almost uniformly diffused while passing through the first diffusion part 191 , the etchant flows between all the wafers W and is almost uniformly supplied to and in contact with all the wafers W. . Accordingly, the etching performance of the wafer W may be improved.

In addition, the etchant discharged from the pressure chamber unit 120 is diffused while passing through the second diffusion unit (193). Since the etchant of the pressure chamber unit 120 is almost uniformly diffused while passing through the second diffusion unit 193 , the discharge rate of the etchant from the entire upper side of the pressure chamber unit 120 may be maintained almost uniformly. In addition, since the high-temperature etching solution of 150-200° C. is diffused while passing through the second diffusion unit 193 in a high-pressure environment of 3-10 bar, evaporation of the etching solution can be suppressed as the high-temperature etching solution is compressed by the high-pressure environment. Accordingly, the etching performance on the upper side of the pressure chamber part 120 may be improved.

In embodiments of the present invention, the etchant may be a silicon nitride etchant, and the silicon nitride etchant may include phosphoric acid and water. At this time, in the composition of the silicon nitride film etchant, the content of water relative to 100 parts by weight of phosphoric acid may be 10 parts by weight to 20 parts by weight, preferably 15 parts by weight to 20 parts by weight, most preferably 85 wt% phosphoric acid and water It may be mixed in an amount of 15 wt%. Hereinafter, an etchant applied to an embodiment of the present invention will be described in detail.

Preparation Example 1. Preparation of a silicon nitride film etchant composition containing a silylphosphine oxide-based compound

(1) Preparation of silylphosphine oxide-based additive compound

A silylphosphine oxide-based compound according to an aspect of the present invention was prepared.

First, H3PO4 anhydride (100%, 300g) and Tetra-Ethyl-Ortho-Silicate (TEOS, 99%, 30g) were mixed and mixed with stirring at 60 rpm for 10 minutes.

Next, the mixture was stirred for 8 hours at 60 rpm at a temperature of 60° C. and reacted first.

Next, after the first reaction was completed, the temperature of the reactor was raised to 120° C., and the second reaction was performed while stirring at 60 rpm for 12 hours.

Next, after the secondary reaction was completed, the temperature of the reactor was raised to 260° C. and stirred at 60 rpm for 3 hours, followed by a third reaction.

Finally, after the tertiary reaction was completed, the temperature of the reactor was cooled to room temperature to obtain a silylphosphine oxide-based compound.

(2) Preparation of a silicon nitride etchant composition containing a silylphosphine oxide-based compound

The silylphosphine oxide-based compound (SiP, 0.1 wt%), phosphoric acid (H3PO4, 85 wt%), water (H2O, 14.8 wt%) and inhibitor (0.1 wt%) prepared in (1) was mixed at room temperature 3 A phosphoric acid etchant composition comprising a silylphosphine oxide-based compound as an additive was prepared by mixing at 60 rpm for a period of time.

Preparation Example 2. Preparation of normal phosphoric acid silicon nitride etchant composition

A phosphoric acid etchant composition was prepared by mixing only phosphoric acid (H3PO4, 85 wt%) and water (H2O, 15.0 wt%) without mixing the (1) silylphosphine oxide-based compound of Preparation Example 1.

Preparation Example 3. Preparation of a silicon nitride film etchant composition containing a silyl phosphate compound

(1) Preparation of silyl phosphate additive compound

A silyl phosphate-based compound according to an aspect of the present invention was prepared.

First, H3PO4 anhydride (100%, 300g) and Tetra-Ethyl-Ortho-Silicate (TEOS, 99%, 30g) were mixed and mixed with stirring at 60 rpm for 10 minutes.

Next, the mixture was stirred at a temperature of 80° C. at 60 rpm for 8 hours and reacted first.

Next, after the first reaction was completed, the temperature of the reactor was raised to 120° C., and the second reaction was performed while stirring at 60 rpm for 12 hours.

Finally, after the secondary reaction was completed, the temperature of the reactor was cooled to room temperature to obtain a silyl phosphate compound.

(2) Preparation of a silicon nitride film etchant composition containing a silyl phosphate compound

The silyl phosphate-based compound (SiOP, 0.05 wt%), phosphoric acid (H3PO4, 85 wt%), water (H2O, 14.85 wt%) and inhibitor (0.1 wt%) prepared in (1) was added at room temperature for 3 hours. By mixing at 60 rpm, a phosphoric acid etchant composition including a silyl phosphate-based compound as an additive was prepared.

Example. Wafer etching using single-wafer etching equipment

In order to evaluate the performance of the single-wafer etching apparatus according to the present invention, using the etchant composition prepared in Preparation Examples 1 to 3 as an etchant and changing the conditions as shown in Table 1 below, a wafer (W) on which a 250 nm silicon nitride film is formed. Etched. At this time, the wafer (W) was etched for 3 minutes each, and the rotation speed was 150 rpm.

[Table 1]

experimental example. Performance evaluation of single-wafer etching equipment

When the wafer (W) is etched under the conditions of Examples 1 to 13 and Comparative Examples 1 to 5, the silicon nitride film etch rate and the silicon oxide film etch rate are measured, and the etch selectivity of the silicon nitride film to the silicon oxide film (silicon nitride film etch rate) /silicon oxide film etch rate) was calculated and shown in Table 2 below.

[Table 2]

As shown in Table 2, in Examples 1 to 13, in which etching was performed under pressure using the single-wafer etching apparatus of the present invention, compared to Comparative Examples 1 to 5 in which etching was performed at 0 bar, conditions other than pressure were higher. In the same case, it was confirmed that the selectivity ratio of the silicon nitride film to the silicon oxide film was excellent.

Example. Wafer Etching Using Batch Etching Equipment

In order to evaluate the performance of the batch etching apparatus according to the present invention, the wafer (W) on which the silicon nitride film is formed with 250 nm is etched by using the etching solution composition prepared in Preparation Examples 1 to 4 as the etching solution and changing the conditions as shown in Table 1 below. did At this time, each wafer W was etched for 20 minutes.

[Table 1]

experimental example. Performance evaluation of batch etching equipment

When the wafer (W) is etched under the conditions of Examples 1 to 12 and Comparative Examples 1 to 7, the silicon nitride film etch rate and the silicon oxide film etch rate are measured, and the etch selectivity of the silicon nitride film to the silicon oxide film (silicon nitride film etch rate) /silicon oxide film etch rate) was calculated and shown in Table 2 below.

[Table 2]

As shown in Table 2, in Examples 1 to 12, in which etching was performed under pressure using the batch etching apparatus of the present invention, compared to Comparative Examples 1 to 7 in which etching was performed at 0 bar, conditions other than pressure In the same case, it was confirmed that the selectivity ratio of the silicon nitride film to the silicon oxide film was excellent.

Since the batch type etching apparatus according to the embodiment of the present invention can prevent vaporization of the etchant, the concentration of the etchant is kept constant, and thus the etch selectivity can be significantly improved.

In addition, since the concentration of the etchant is kept constant due to pressurization, additional input of deionized water and etchant to maintain the concentration is not required. In terms of cost, it can be greatly reduced.

Although the present invention has been described with reference to the embodiment shown in the drawings, this is merely exemplary, and it is understood that various modifications and equivalent other embodiments are possible by those of ordinary skill in the art. will understand

Accordingly, the true technical protection scope of the present invention should be defined by the claims.

100: etching device 110: carrier
111: carrier driving unit 113: gripper
115: wafer holder 120: pressure chamber unit
121: inner chamber portion 122: pressure chamber
123: outer chamber portion 125: extension plate portion
127: vent unit 130: door
140: guide unit 141: guide bar
143: connection member 144: restraint rib
150: door restraint 151: restraint clamp
153: clamp driving unit 160: door driving unit
161: stator 163: mover
170: visual solution supply unit 171: etchant storage tank
173: etchant circulation pipe part 174: first circulation pipe part
174a: supply port 175: second circulation pipe part
175a: discharge port 176: opening control valve
177: circulation driving unit 181: pressing unit
182: temperature control unit 183: exhaust unit
191: first diffusion unit 191a: first diffusion hole portion
193: second diffusion unit 193a: second diffusion hole portion

Claims (20)

a pressure chamber in which one or more wafers are accommodated;
a door installed in the pressure chamber to open and close the pressure chamber;
a guide part connected to the door and the pressure chamber part to guide the movement of the door;
a door restraint part for restraining at least one of the guide part and the door so that the door closes the pressure chamber part to maintain the door in a compressed state in the pressure chamber part; and
and an etchant supply unit connected to the pressure chamber to supply the etchant to the pressure chamber in a state in which the door closes the pressure chamber.
According to claim 1,
The guide part is connected to the door so as to move together with the door, and is installed on both sides of the pressure chamber part.
3. The method of claim 2,
The guide unit,
a plurality of guide bars connected to both sides of the door and movably installed in the pressure chamber; and
and a connecting member connected to the plurality of guide bars and constrained to the door restraint unit.
3. The method of claim 2,
The door restraint unit,
a restraining clamp disposed on a side surface of the pressure chamber; and
and a clamp driving part connected to the restraining clamp and moving the restraining clamp to restrain the guide part.
5. The method of claim 4,
The restraining clamp is an etching apparatus, characterized in that disposed on both sides of the pressure chamber portion, respectively.
6. The method of claim 5,
An etching apparatus, characterized in that two clamp driving units are respectively connected to both sides of the restraining clamp.
3. The method of claim 2,
The door restraint unit,
a restraining clamp disposed on a side surface of the pressure chamber; and
and a clamp driving part connected to the restraining clamp and moving the restraining clamp to restrain the door.
8. The method of claim 7,
The restraining clamp is an etching apparatus, characterized in that disposed on both sides of the pressure chamber portion, respectively.
9. The method of claim 8,
The etching apparatus, characterized in that the clamp driving unit is connected one by one for each of the restraining clamps.
According to claim 1,
The etching apparatus according to claim 1, further comprising a door driving unit installed in the pressure chamber to move the door.
According to claim 1,
The etchant supply unit,
An etchant storage tank in which the etchant is stored;
an etchant circulation pipe connected to the etchant storage tank and the pressure chamber to supply the etchant to the inside of the pressure chamber; and
Etching apparatus comprising a circulation driving part connected to the etchant circulation pipe part.
12. The method of claim 11,
The supply port of the etchant circulation pipe part is connected to the lower side of the pressure chamber part,
The discharge port of the etchant circulation pipe part is an etching apparatus, characterized in that connected to the upper side of the pressure chamber part.
13. The method of claim 12,
The pressure chamber part etching apparatus characterized in that it further comprises a first diffusion part disposed under the pressure chamber part to diffuse the etchant introduced through the supply port.
14. The method of claim 13,
The pressure chamber part etching apparatus characterized in that it further comprises a second diffusion part disposed above the pressure chamber part to diffuse the etchant discharged from the inside of the pressure chamber part to the discharge port.
A step of putting the wafer into the pressure chamber;
closing the pressure chamber part as the door is moved by the guide part;
constraining at least one of the guide part and the door when the pressure chamber part of the door is closed to keep the door pressed to the pressure chamber part; and
The control method of an etching apparatus comprising the step of supplying an etching solution to the pressure chamber by the etching solution supply unit.
16. The method of claim 15,
In the step of maintaining the door pressed to the pressure chamber part when the pressure chamber part of the door is closed,
In the door restraint portion provided with a restraint clamp disposed on a side surface of the pressure chamber and a clamp driving unit for moving the restraint clamp, the restraint clamp restrains the guide part.
16. The method of claim 15,
In the step of maintaining the door pressed to the pressure chamber part when the pressure chamber part of the door is closed,
In the door restraint portion provided with a restraint clamp disposed on a side surface of the pressure chamber and a clamp driving unit for moving the restraint clamp, the restraint clamp restrains both sides of the door.
16. The method of claim 15,
In the step of the etchant supply unit supplying the etchant to the pressure chamber,
Control method of an etching apparatus, characterized in that circulating the etchant to the pressure chamber and the etchant storage tank through the etchant supply unit.
18. The method of claim 17,
In the step of the etchant supply unit supplying the etchant to the pressure chamber,
The control method of the etching apparatus, characterized in that the etchant flowing into the pressure chamber is diffused while passing through the first diffusion.
20. The method of claim 19,
In the step of the etchant supply unit supplying the etchant to the pressure chamber,
The control method of the etching apparatus, characterized in that the etchant discharged from the pressure chamber is diffused while passing through the second diffusion.

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