TWI759963B - Plasma processing apparatus and heater thereof - Google Patents

Abstract

The invention discloses a plasma processing device and a heater thereof. The heater is arranged on an insulating material window of the plasma processing device. The heater includes a first sub-heater and a second sub-heater, and the first sub-heater includes a first insulating plate. and a first heating wire arranged above the first insulating plate, the second sub-heater includes a second insulating plate and a second heating wire arranged on the second insulating plate; the first heating wire and the second heating wire are connected in series It is connected to a heating power source, and the current direction generated by the heating power source in the first heating wire is opposite to the current direction generated by the second heating wire. The induced current generated by the high-frequency magnetic field passing through the first heating wire and the induced current generated when passing through the second heating wire can just cancel each other out, thereby avoiding the problem of power loss of the radio frequency coil caused by the heater.

Description

Plasma processing device and heater thereof

The present invention relates to the technical field of etching, and in particular, to a plasma processing device and a heater thereof.

With the development of semiconductor manufacturing process, the requirements for the integration and performance of components are getting higher and higher, and the plasma process is widely used in the manufacture of semiconductor devices. The main plasma processing devices include capacitive coupling (CCP) and inductive coupling (ICP). The inductive coupling plasma processing device has the advantages of high plasma concentration and fast etching rate, and is currently widely used.

For the plasma processing device, its structure mainly includes a reaction chamber, the top of the reaction chamber is provided with an insulating material window, and the bottom of the reaction chamber is provided with a base, and the base is used to place the substrate to be processed, A low-frequency radio frequency power supply is connected to the base through a matching device, and the upper surface of the insulating material window also includes a heating coil, which is used to control the temperature of the insulating material window, because the temperature of the insulating material window will affect the reaction in the reaction chamber. The uniformity of the speed and the temperature gradient on the insulating material window may even cause cracking and damage of the insulating material window. The heating coil is wired to a heating power source. At least one induction coil is arranged above the heating coil, and the induction coil is connected with a high-frequency radio frequency power supply. High-frequency radio frequency power is applied to the induction coil to generate a high-frequency magnetic field. These high-frequency magnetic fields pass down the heating coil and the insulating material window and enter the reaction chamber. The high-frequency magnetic field induces a high-frequency electric field, and the high-frequency electric field excites the reaction chamber. The reactive gases generate and maintain the desired plasma.

These high-frequency magnetic fields can not only generate an induced electric field in the reaction chamber, but also induce an induced current in the heating coil. Since these heating coils generate an induced current, they will consume a certain amount of energy, which will affect the induction coil (radio frequency coil). power loss.

To sum up, how to solve the problem of reducing the loss of radio frequency power has become a technical problem that those skilled in the art need to solve urgently.

The purpose of the present invention is to provide a plasma processing device and a heater thereof to solve the problem of reducing the loss of radio frequency power.

In order to achieve the above object, the present invention provides a heater of a plasma processing device, the heater is arranged on an insulating material window of the plasma processing device, the heater includes a first sub-heater and a second sub-heater, so The first sub-heater includes a first insulating plate and a first heating wire disposed above the first insulating plate, and the second sub-heater includes a second insulating plate and a heating wire disposed on the second insulating plate. the second heating wire;

The first heating wire and the second heating wire have the same shape and are aligned up and down, the first heating wire and the second heating wire are connected to a heating power source in series with each other, and the heating The direction of the current generated by the power source at the first heating wire is opposite to the direction of the current generated by the heating power source at the second heating wire.

Preferably, both the first insulating plate and the second insulating plate are ceramic plates.

Preferably, the number of the heaters is multiple, and the heaters are coaxially stacked.

Preferably, a plurality of the heaters are connected in parallel or in series on the same heating power source.

Preferably, the first heating wire and the second heating wire are both flat and spiral.

Preferably, the heating power source is an AC heating power source.

Preferably, the first heating wire is fixed on the first insulating plate by means of thermally conductive adhesive.

Preferably, the second heating wire is fixed on the second insulating plate by means of thermally conductive adhesive.

Preferably, the first sub-heater and the second sub-heater are fixedly connected by thermally conductive glue.

Compared with the content introduced in the prior art, the heater of the above-mentioned plasma processing apparatus is arranged on the insulating material window of the plasma processing apparatus, and the heater includes a first sub-heater and a second sub-heater, and the first sub-heater includes a first insulating material. plate and a first heating wire arranged above the first insulating plate, the second sub-heater includes a second insulating plate and a second heating wire arranged on the second insulating plate; the shapes of the first heating wire and the second heating wire The first heating wire and the second heating wire are connected to the heating power source in series with each other, and the current loop generated by the heating power source in the first heating wire is the same as the current generated by the heating power source in the second heating wire. The current circulates in the opposite direction. By arranging the above-mentioned heater in the plasma processing device, in the actual working process, since the first heating wire and the second heating wire of the heater have the same shape and are aligned up and down, they are connected to each other in series. Heating the power supply, and the current direction generated by the heating power supply on the first heating wire is opposite to the current direction generated on the second heating wire, that is, when the current in the same direction flows through the first heating wire and the second heating wire, The current direction of the first heating wire is opposite to the current direction of the second heating wire, and since the shape of the first heating wire and the second heating wire are the same, when the high-frequency magnetic field generated by the radio frequency coil passes through the first heating wire When it is connected to the second heating wire, the magnetic flux of the closed loop formed by the first heating wire and the second heating wire is close to zero, and the induced current generated by the high-frequency magnetic field passing through the first heating wire is different from that generated when passing through the second heating wire. The induced currents just cancel each other out. Thus, the problem of power loss of the radio frequency coil caused by the heater is effectively avoided. In addition, with the structure of disposing insulating plates under the first heating wire and under the second heating wire, the risk of arcing between the first heating wire and the second heating wire can be effectively avoided, and at the same time, it is helpful to improve the The heating uniformity of the heater. Among them, the uniformity is mainly reflected in the fixed connection of the two-layer sub-heater. Generally, a thermally conductive adhesive can be selected. The overall heater is arranged in the middle of the entire insulating window, and the overall heating effect will be better. By setting two layers of sub-heating The structure of the heater removes the restriction that the spacing of heating wires on a single heater cannot be too large, so at the same time, the risk of arcing caused by too dense heating wires is reduced. Because a single heater can only reduce the area of the closed-loop magnetic flux by arranging it closely, and arranging too densely has the risk of arcing.

In addition, the present invention also provides a plasma processing apparatus, comprising a heater structure, and the heater structure is the heater structure described in any of the above means. Since the above-mentioned heater structure has the above-mentioned technical effect, the plasma processing apparatus having the above-mentioned heater structure should also have the corresponding technical effect, which will not be repeated here.

In addition, the present invention also provides a heater for a plasma processing device, the heater is arranged in an insulating material window of the plasma processing device, the heater includes a first heating wire and a second heating wire, the first heating wire and the second heating wire The heating wires have the same shape and are aligned with a preset distance up and down. The first heating wire and the second heating wire are connected to the heating power supply in series with each other, and the current direction generated by the heating power supply in the first heating wire is related to the heating power. The current produced by the power source in the second heating wire is in the opposite direction.

By arranging the heater in the insulating material window of the plasma processing device, it means that the heater is completely or partially embedded in the insulating material window, for example, a layer of heating wire is buried in the insulating material window in the middle of the entire insulating window, and another layer is embedded in the insulating material window. The heating wire is arranged on the top surface of the insulating material window. This arrangement makes the overall heating uniformity effect better.

The core of the present invention is to provide a plasma processing device and a heater thereof to solve the problem of reducing the loss of radio frequency power.

In order to make those skilled in the art better understand the technical means provided by the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

As shown in Figures 1 and 2, a heater structure of a plasma processing apparatus provided by an embodiment of the present invention includes a heater 1 disposed on an insulating material window of the plasma processing apparatus, and the heater 1 includes a first sub-heater heater 11 and second sub-heater 12, the first sub-heater 11 includes a first insulating plate 111 and a first heating wire 112 disposed above the first insulating plate 111, and the second sub-heater 12 includes a second insulating plate 121 and the second heating wire 122 disposed on the second insulating plate 121; the first heating wire 112 and the second heating wire 122 have the same shape and are aligned up and down, and the first heating wire 112 and the second heating wire 122 are mutually It is connected to the heating power source 2 in series, and the direction of the current generated by the heating power source 2 in the first heating wire 112 is opposite to the direction of the current generated by the heating power source 2 in the second heating wire 122 .

By arranging the above-mentioned heater structure 1 in the plasma processing apparatus, in the actual working process, since the first heating wire 112 and the second heating wire 122 of the heater 1 have the same shape and are aligned up and down, and are mutually It is connected to the heating power source 2 in series, and the current direction generated by the heating power source 2 on the first heating wire 112 is opposite to the current direction generated on the second heating wire 122, that is, the current in the same direction is flowing through the first heating wire 122. When the heating wire 112 and the second heating wire 122 are heated, the current direction of the first heating wire 112 is opposite to the current direction of the second heating wire 122, and since the shapes of the first heating wire 112 and the second heating wire 122 are the same, therefore , when the high-frequency magnetic field generated by the radio frequency coil 3 passes through the first heating wire 112 and the second heating wire 122, the closed-loop magnetic flux formed by the first heating wire 112 and the second heating wire 122 is close to zero, and the high-frequency magnetic field The induced current generated when passing through the first heating wire 112 and the induced current generated when passing through the second heating wire 122 can just cancel each other out. Thus, the problem of power loss of the radio frequency coil 3 caused by the heater 1 is effectively avoided. In addition, by disposing insulating plates under both the first heating wire 112 and the second heating wire 122, the risk of arcing between the first heating wire 112 and the second heating wire 122 can be effectively avoided, and the Helps to improve the heating uniformity of the heater 1 . Among them, the uniformity is mainly reflected in the fixed connection of the two-layer sub-heater. Generally, a thermally conductive adhesive can be selected. The overall heater 1 is arranged in the middle of the entire insulating window, and the overall heating effect will be better; The structure of the heater removes the restriction that the spacing of heating wires on a single heater cannot be too large, so at the same time, the risk of arcing caused by too dense heating wires is reduced. Because a single heater can only reduce the area of the closed-loop magnetic flux by arranging finely, and arranging too densely has the risk of arcing.

It should be noted that those skilled in the art should be able to understand that the direction of the current generated by the heating power source 2 in the first heating wire 112 is opposite to the direction of the current generated by the heating power source 2 in the second heating wire 122. The direction refers to the direction of the current flow path on the first heating wire and the second heating wire, respectively. Moreover, in order to realize the opposite direction of the flow path, the specific structural form in which the first heating wire 112 and the second heating wire 122 are connected in series with each other is that the head end of the first heating wire 112 and the head end of the second heating wire 122 are electrically connected, and the first heating wire 112 and the head end of the second heating wire 122 are electrically connected. The tail end of the heating wire 112 is electrically connected to the tail end of the second heating wire 122 , wherein the first heating wire 112 and the second heating wire 122 arranged vertically aligned include a head end and a tail end. The head end and the head end are aligned up and down, and the tail end is aligned with the tail end.

In addition, it should be noted that, the above-mentioned first insulating plate 111 and second insulating plate 121 are preferably made of ceramic plates. Because the ceramic plate has good thermal insulation performance and uniformity of heat conduction. The heating uniformity of the heater 1 is more favorable by setting it as a ceramic material. Of course, it can be understood that the above method of using ceramic plates is only a preferred example of the embodiment of the present invention. In the actual application process, insulating plates of other materials commonly used by those skilled in the art can also be selected, which are not described here. limited.

In some specific implementation means, the number of the above-mentioned heaters 1 may be selected to be multiple, or only one of the heaters 1 may be selected.

In a further implementation means, when choosing the way of arranging multiple heaters, multiple heaters 1 are preferably connected in parallel or in series on the same heating power supply 2, because by being connected in parallel on the same heating power supply 2, it is more advantageous. The temperature consistency and uniformity of heating by each heater 1. Of course, it can be understood that, in the actual application process, it is also possible to select an independent heating power supply 2 for each heater 1 according to actual needs, or some heaters 1 are connected in parallel to one heating power supply 2, and some heaters 1 are independent. The heating power supply 2 can be arranged according to the actual heating demand in practical applications; of course, it is understandable that when precise control of each heater 1 is required, it is also possible to choose an independent heating power supply 2 for each heater 1 .

It should be noted here that, generally speaking, the above-mentioned first heating wire 112 and second heating wire 122 are preferably designed in a plane spiral structure. Of course, it can be understood that the heating wire using the plane spiral structure is only a preferred example of the embodiment of the present invention, and other shapes can also be selected according to actual requirements during practical application.

In addition, it should be noted that, in general, the above-mentioned heating power source 2 is preferably an AC heating power source. Of course, it can be understood that a DC heating power source can also be selected according to actual needs in the actual application process.

In addition, it should be noted that, in general, the first heating wire 112 is fixed on the first insulating plate 111 by means of thermally conductive adhesive; the second heating wire 122 is fixed on the second insulating plate by means of thermally conductive adhesive. on board 121. Of course, it can be understood that the above-mentioned fixing of the heating wire and the insulating plate by means of thermally conductive adhesive is only a preferred example of the embodiment of the present invention. In the actual application process, other fixing methods commonly used by those skilled in the art can also be selected. , such as the manner in which the heating wire is partially embedded in the insulating plate, etc., which are not specifically limited here.

In addition, it should be noted that, in order to ensure the uniformity of the overall heating of the heater, the first sub-heater and the second sub-heater are preferably bonded and fixed with a thermally conductive adhesive. And when the number of heaters is multiple, it is generally preferable to bond and fix two adjacent heaters with thermally conductive adhesive.

In addition, the present invention also provides a heater 1 of a plasma processing device. The heater 1 is arranged in an insulating material window of the plasma processing device. The heater 1 includes a first heating wire 112 and a second heating wire 122. The first heating wire 112 and the second heating wire 122 have the same shape and are aligned with the upper and lower intervals by a preset distance. The first heating wire 112 and the second heating wire 122 are connected to the heating power source 2 in series with each other, and the heating power source 2 is in the first heating. The direction of the current generated in the wire 112 is opposite to the direction of the current generated by the heating power source 2 in the second heating wire 122 .

By arranging the heater 1 in the insulating material window of the plasma processing device, specifically, the heater 1 is fully or partially embedded in the insulating material window, for example, a layer of heating wire is buried in the insulating material window in the middle of the entire insulating window, Another layer of heating wire is arranged on the top surface of the insulating material window. This arrangement makes the overall heating uniformity effect better. Of course, it can be understood that, in the actual application process, the entire first heating wire 112 and the second heating wire 122 may also be embedded inside the insulating material window.

In addition, the present invention also provides a plasma processing apparatus, comprising a heater structure, and the heater structure is the heater structure described in any of the above means. Since the above-mentioned heater structure has the above-mentioned technical effect, the plasma processing apparatus having the above-mentioned heater structure should also have the corresponding technical effect, which will not be repeated here.

The plasma processing apparatus and the heater thereof provided by the present invention have been described in detail above. It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. For the same and similar parts among the various embodiments, refer to each other Can.

It should also be noted that, herein, terms such as "comprising", "comprising" or any other variation thereof are intended to encompass non-exclusive inclusion, whereby an article or device comprising a list of elements includes not only those elements, but also Include other elements not expressly listed, or elements inherent to the article or equipment. Without further limitation, an element defined by the phrase "comprising a..." does not preclude the presence of additional identical elements in an article or device that includes the above-mentioned element.

The principles and implementations of the present invention are described herein by using specific examples, and the descriptions of the above embodiments are only used to help understand the core idea of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can also be made to the present invention, and these improvements and modifications also fall within the protection scope of the patented scope of the present invention. .

1: heater 2: Heating power supply 3: RF coil 11: The first sub heater 12: Second sub heater 111: The first insulating plate 112: The first heating wire 121: Second insulating plate 122: Second heating wire

FIG. 1 is a schematic structural diagram of a heater of an ion processing apparatus provided by an embodiment of the present invention; FIG. 2 is a schematic diagram of a series structure of the first heating wire and the second heating wire after unfolding according to an embodiment of the present invention, and the arrows in the figure represent the current flow.

1: heater

3: RF coil

11: The first sub heater

12: Second sub heater

111: The first insulating plate

112: The first heating wire

121: Second insulating plate

122: Second heating wire

Claims (11)

A heater for a plasma processing device, wherein the heater is arranged on an insulating material window of the plasma processing device, the heater includes a first sub-heater and a second sub-heater, the first sub-heater includes a a first insulating plate and a first heating wire arranged above the first insulating plate, the second sub-heater includes a second insulating plate and a second heating wire arranged on the second insulating plate; The first heating wire and the second heating wire have the same shape and are aligned up and down. The first heating wire and the second heating wire are connected to a heating power source in series with each other, and the heating power source is in the first heating wire. The direction of the current generated by one heating wire is opposite to the direction of the current generated by the heating power source on the second heating wire. The heater of the plasma processing apparatus according to claim 1, wherein the first insulating plate and the second insulating plate are both ceramic plates. The heater of the plasma processing apparatus according to claim 1, wherein the number of the heaters is plural, and the heaters are coaxially stacked. The heater of the plasma processing apparatus according to claim 3, wherein a plurality of the heaters are connected in parallel or in series to the same heating power source. The heater for a plasma processing apparatus according to any one of claim 1 to claim 4, wherein the first heating wire and the second heating wire are both planar and helical. The heater of the plasma processing apparatus according to any one of claim 1 to claim 4, wherein the heating power source is an alternating current heating power source. The heater for a plasma processing apparatus according to any one of claim 1 to claim 4, wherein the first heating wire is fixed on the first insulating plate by means of thermally conductive adhesive. The heater of the plasma processing apparatus according to any one of claim 1 to claim 4, wherein the second heating wire is fixed on the second insulating plate by means of bonding. The heater of a plasma processing apparatus according to any one of claim 1 to claim 4, wherein the first sub-heater and the second sub-heater are fixedly connected by thermally conductive glue. A plasma processing apparatus includes a heater structure, wherein the heater structure is the heater according to any one of claim 1 to claim 9. A heater for a plasma processing device, wherein the heater is arranged in an insulating material window of the plasma processing device, the heater comprises a first heating wire and a second heating wire, the first heating wire and the second heating wire The wires have the same shape and are aligned at a predetermined distance up and down. The first heating wire and the second heating wire are connected to a heating power source in series with each other, and the heating power source generates a current in the first heating wire. The direction is opposite to the direction of the current generated by the heating power source in the second heating wire.

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