JP4179592B2 - Substrate peripheral processing apparatus and substrate peripheral processing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a substrate peripheral processing apparatus and a substrate peripheral for supplying an etching solution to the peripheral portion of the substrate surface and removing unnecessary materials (thin films, particles, ions, etc., especially metal films and metal ions) on the peripheral portion. It relates to the processing method. The substrates to be processed include various substrates such as semiconductor wafers, glass substrates for liquid crystal display devices, glass substrates for plasma display panels, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, and photomask substrates. included.
[0002]
[Prior art]
In the manufacturing process of a semiconductor device, a metal thin film such as a copper thin film is formed over the entire surface of a semiconductor wafer (hereinafter simply referred to as “wafer”) and the peripheral end surface (in some cases, the back surface). In some cases, unnecessary portions are removed by etching. For example, since the copper thin film for forming the wiring only needs to be formed in the element formation region on the front surface of the wafer, the peripheral portion of the wafer surface (for example, a portion having a width of about 5 mm from the peripheral edge of the wafer), the back surface and The copper thin film formed on the peripheral end surface is not necessary. In addition, copper or copper ions on the peripheral edge, back surface, and peripheral edge surface contaminate the hand of the substrate transfer robot provided in the substrate processing apparatus, and this contamination is further transferred to another wafer held by the hand. Causes the problem of metastasis.
[0003]
For the same reason, there is a process for removing metal contaminants (including metal ions) on the surface by thinly etching a film (such as an oxide film or a nitride film) other than the metal film formed on the periphery of the wafer. Sometimes done.
As shown in FIG. 18, for example, as shown in FIG. 18, a substrate peripheral processing apparatus for selectively etching the peripheral edge and peripheral thin film on the peripheral edge of the wafer holds the wafer W horizontally and rotates it around a vertical axis. The etching liquid supply nozzle 101 supplies an etching liquid toward the peripheral edge of the wafer W, and the pure water supply nozzle 102 supplies pure water toward the center of the wafer W.
[0004]
With this configuration, the etchant is supplied from the etchant supply nozzle 101 while rotating the wafer W by the spin chuck 100, so that the etchant supply position 105 (the etchant from the etchant supply nozzle 101) at the peripheral edge of the wafer W is supplied. The etching solution spreads from the vicinity of the position of the outer peripheral portion to the peripheral region of a predetermined width (for example, 3 to 5 mm) on the outer side in the rotational radius direction, and the thin film 107 in this region is removed by etching.
[0005]
At the same time, by supplying pure water from the pure water supply nozzle 102 to the center of the wafer W, even if the etchant bounces back to the central area (device formation area) of the wafer W, the etching liquid is quickly supplied. It can be washed away and the central area can be protected.
[0006]
[Problems to be solved by the invention]
The etching solution supply nozzle 101 is configured to discharge the etching solution from, for example, a discharge port 108 having a diameter of about 0.5 mm. The etching solution supply nozzle 101 excludes pure water supplied from the pure water supply nozzle 102, and the surface of the wafer W is removed. A flow velocity that can reach the thin film 107 can be secured.
Therefore, in the peripheral portion of the wafer W, the progress of the etching at the etching solution supply position 105 is fast, and the progress of the etching process on the radially outer side is slower than that. Even when pure water is not supplied from the pure water supply nozzle 102, the same tendency is observed. However, when pure water is supplied from the pure water supply nozzle 102, the tendency becomes more remarkable. This is because the concentration of the etching solution is the highest at the etching solution supply position 105, and the concentration of the etching solution becomes thinner due to dilution with pure water toward the outer side in the rotational radius direction. Conceivable.
[0007]
Thus, since the progress of the etching process is slower toward the outer peripheral side of the wafer W in the peripheral portion of the wafer W, the removal efficiency of the thin film 107 is poor, and it takes time to etch and remove the thin film 107 in the entire peripheral region. There was a problem of poor productivity.
SUMMARY OF THE INVENTION An object of the present invention is to provide a substrate periphery processing apparatus and a substrate periphery processing method that can efficiently remove unnecessary materials on the periphery of a substrate.
[0008]
[Means for Solving the Problems and Effects of the Invention]
  The invention described in claim 1 for achieving the above object is a substrate peripheral processing apparatus for supplying an etching solution to a peripheral portion of a substrate (W) and etching away unnecessary materials on the peripheral portion. Substrate rotating means (1) for rotating the substrate about a rotation axis (1a) passing through substantially the center of the substrate and substantially perpendicular to the substrate surface, and a distance from the rotation axis of the substrate at the peripheral edge of the substrateIs differentThe same kind of etching solution is supplied toward a plurality of positions (46).MultipleDischarge ports (42, 42S, 72, 72S, 92, 92S, 98)Nozzle body(4, 70, 90, 95)Nozzle bodyofAboveEtching protection liquid supply means (5) for supplying an etching protection liquid toward an inner position from a supply position closest to the rotation axis among the etching liquid supply positions from the discharge port.The nozzle body has a substrate facing surface (41, 71, 91, 96) facing the surface of the substrate, and the plurality of discharge ports are opened in the substrate facing surface. Is disposed in close proximity to the substrate so as to contact the etching solution supplied to the peripheral portion of the substrate and form a liquid film (48) between the substrate-facing surface and the peripheral portion of the substrate. ingThis is a substrate peripheral edge processing apparatus. The alphanumeric characters in parentheses indicate corresponding components in the embodiments described later. The same applies hereinafter.
[0009]
  According to the above configuration, while the substrate is rotated,From a plurality of outlets provided in the nozzle body,At the periphery of the boardsubstrateDistance from the rotation axisIs differentSince the same kind of etching solution is supplied toward a plurality of positions, the etching process at the peripheral edge of the substrate proceeds substantially uniformly in the rotational radius direction. Thereby, the removal efficiency of the unnecessary thing in the peripheral part of a board | substrate can be improved, and the productivity of a board | substrate peripheral process can be improved by extension.
  In addition, the central region of the substrate can be surely protected by the etching protection liquid, and the etching liquid is supplied at different positions with respect to the rotation radius direction at the peripheral portion of the substrate. Even if the etching protection liquid is poured, the concentration of the etching liquid at the peripheral edge of the substrate can be kept substantially uniform in the rotational radius direction. As a result, the rate of progress of the etching process in the rotational radius direction becomes substantially uniform, so that the peripheral edge of the substrate can be processed efficiently and good productivity can be secured..
  Examples of the etching protection liquid are pure water, carbonated water, hydrogen water, reduced water, ionic water, magnetic water, and the like.
  The unnecessary matter to be removed from the peripheral edge of the substrate may be a thin film (for example, a metal thin film such as a copper thin film), particles or ions (particularly metal ions such as copper ions).
[0010]
The substrate rotating means may rotate the substrate while being held substantially horizontal. Specifically, the substrate rotating means may include a spin chuck that rotates while holding the substrate from one surface side. The spin chuck may be a vacuum chuck that holds one surface of the substrate by suction, or may be a mechanical chuck that sandwiches the end surface of the substrate with a plurality of chuck pins.
The plurality of positions to which the etching solution is supplied may be separated (that is, may be scattered), or may be continuous in a linear shape, for example. When the etching solution supply positions are scattered, the plurality of etching solution supply positions are adjacent to each other so that the liquid films of the etching solution supplied toward the respective positions are coupled to each other at the peripheral edge of the substrate. It is preferable that things are close enough.
[0011]
  ContractClaim6As described aboveMultiple outletsOpens in a slit shapeVomitingWith exit (42S, 72S, 92S)AndAlso good.
[0012]
  Having the plurality of discharge portsThere may be one nozzle body or multiple nozzle bodies.ProvidedGood.
[0013]
  In the present invention,The nozzle body is opposed to the substrate facing the surface of the substrate (preferably substantially parallel).FaceAnd have the above-mentioned surface facing the substratepluralThe discharge port is openThe AndThe substrate facing surface is in contact with the etching solution supplied to the peripheral portion of the substrate, and a liquid is provided between the substrate facing surface and the peripheral portion of the substrate.MembraneIs placed close to the substrate so as to formTheFor example, by setting the distance between the substrate facing surface and the substrate to 0.3 mm to 3 mm, the substrate facing surface can be brought into contact with the liquid film of the etching solution on the substrate.
[0014]
  According to this configuration, a liquid film of the etching liquid can be formed between the nozzle body and the peripheral edge portion of the substrate, and this liquid film comes into contact with the substrate facing surface of the nozzle body and is stabilized. As a result, the progress of the etching process at the peripheral edge of the substrate can be made more uniform, and the processing width of the etching process can be accurately controlled.
Claim2The invention described in the above is characterized in that the inner edge of the substrate facing surface is formed in an arc shape along the inner periphery of the processing target region at the periphery of the substrate.1It is a board | substrate periphery processing apparatus of description.
  Claim3In the described invention, the substrate facing surface is formed along a tangential direction of the rotation direction of the substrate,WritingThe number of ejection openings are densely arranged near the central portion of the tangential direction of the substrate facing surface, and are roughly arranged near the end portion.1 or 2It is a board | substrate periphery processing apparatus of description.
  Claim4The invention described is the aboveMultiple2. The discharge port for supplying an etching solution toward a plurality of positions arranged in a substantially straight line at the peripheral edge of the substrate.3The substrate peripheral edge processing apparatus according to any one of the above.
[0015]
  With this configuration, while the substrate is rotated, the etching solution supply positions are arranged in a straight line, so that the etching solution can be supplied to a plurality of positions having different distances from the rotation center. The straight line in which the etching solution supply positions are arranged may be, for example, along the tangential direction of the rotation of the substrate.
  Claims5As described aboveMultipleThe discharge port may supply an etching solution toward a plurality of positions arranged on an arc having a center of curvature at a position deviated from the rotation center of the substrate at the peripheral edge of the substrate.
[0016]
When the substrate has a substantially circular outer peripheral edge, the radius of curvature of the arc is preferably different from the radius of the outer peripheral edge of the substrate. Furthermore, it may be different from the radius of curvature of the inner periphery of the processing target region (ring-shaped region) at the peripheral portion of the substrate. However, as long as the center of curvature of the arc in which a plurality of etching solution supply positions are aligned and the center of curvature of the outer peripheral edge of the substrate are shifted, the radius of curvature of the arc may be equal to the radius of curvature of the outer peripheral edge of the substrate, It may be equal to the radius of curvature of the inner peripheral edge of the processing target area at the peripheral edge of the substrate.
[0017]
  And claims7As described aboveMultipleThe discharge port may supply the etching solution toward a plurality of positions arranged so as to surround the rotation axis of the substrate at the peripheral edge of the substrate.
  In this case, the plurality of supply positions of the etching solution may be arranged along an elliptical circumference, or may be arranged along a circumference centered on a point different from the rotation center of the substrate, You may arrange | position along each side of a polygon. Of course, a zigzag arrangement may be used.
  More specifically, the aboveMultipleThe discharge port may supply the etching solution toward a plurality of positions arranged along each side of the polygon.8).
  Also, aboveMultipleThe discharge port may supply the etching solution toward a plurality of positions arranged along the elliptical circumference.9).
  In addition, the aboveMultipleThe discharge port may supply the etching solution toward a plurality of positions arranged along a circumference centered on a point different from the rotation center of the substrate.10).
[0018]
  the aboveNozzle bodyIf the substrate facing surface over the circumference of the peripheral portion of the substrate is provided and the liquid film of the etching solution at the peripheral portion of the substrate is in contact with the substrate facing surface, the etching processing width at the peripheral portion of the substrate can be increased. It becomes possible to control the entire circumference. That is, the peripheral edge of the substrate can be processed with a precisely controlled processing width by appropriately arranging the inner edge of the substrate facing surface according to the etching processing width..
[0019]
  Claim11The invention described is the aboveMultipleThe discharge port supplies the etching solution to the peripheral edge of the substrate along a direction perpendicular to the substrate or a direction inclined toward the outside of the substrate. Or10The substrate peripheral edge processing apparatus according to any one of the above.
  According to this configuration, the etching solution can be suppressed or prevented from entering the central region (device forming region) of the substrate.
[0021]
  Claim12The described invention is a substrate peripheral processing method for supplying an etching solution to a peripheral portion of a substrate (W) and etching away unnecessary materials on the peripheral portion, and passes the substantially center of the substrate to the substrate surface. A substrate rotation step of rotating the substrate about a substantially orthogonal rotation axis (1a), and at the periphery of the substrate during the substrate rotation step,From a nozzle body having a plurality of discharge ports,Distance from the rotation axis of the boardIs differentAn etching solution supplying step for supplying the same kind of etching solution toward the plurality of positions (46), and the rotation axis among the plurality of positions at which the etching solution is supplied on the substrate surface during the substrate rotation step. An etching protection liquid supply step for supplying an etching protection liquid toward an inner position from a supply position closest toThe nozzle body has a substrate facing surface that faces the surface of the substrate, and the plurality of discharge ports are opened in the substrate facing surface. The substrate facing surface is disposed close to the substrate so as to form a liquid film between the substrate facing surface and the peripheral portion of the substrate in contact with the etching solution supplied to the peripheral portion of the substrate. Including the process ofThis is a substrate peripheral edge processing method.
[0022]
  By this method, the same effect as in the case of the invention of claim 1 can be achieved.
In any of the claims, the etching solution supply position at the peripheral edge of the substrate may be changed with time.
  More specifically, for example, NoThe slip body may be reciprocated or oscillated. That is, the nozzle body may be reciprocated along the tangential direction of the substrate rotation, or the nozzle body may be reciprocated or oscillated along the rotation radius direction of the substrate. Further, the etching solution supply position may be changed with time by rotating the nozzle body and changing the discharge direction of the etching solution from the discharge port.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a perspective view schematically showing a configuration of a substrate peripheral edge processing apparatus according to an embodiment of the present invention. This substrate peripheral processing apparatus is an apparatus for etching away unnecessary materials on the peripheral portion of the surface (device forming surface) of a semiconductor wafer (hereinafter simply referred to as “wafer”) W, which is a substantially circular substrate. The unnecessary materials to be removed include metal films such as a copper thin film, particles, metal ions such as copper ions, and the like.
[0024]
The substrate peripheral edge processing apparatus includes a spin chuck 1 that holds a wafer W in a horizontal posture with the surface facing upward, and rotates around a vertical axis 1 a that passes through substantially the center of the wafer W. The spin chuck 1 is composed of, for example, a vacuum chuck that sucks and holds the central portion of the lower surface of the wafer W, and a rotary drive mechanism 3 including a motor or the like on a rotary shaft 2 arranged along the vertical direction. The rotational force from is given.
[0025]
The substrate peripheral processing apparatus further performs etching for removing unnecessary materials on the peripheral portion (non-device forming region around the device forming region) of the wafer W held by the spin chuck 1 and rotated around the vertical axis 1a. An etching solution supply nozzle 4 for supplying a solution and a pure water supply nozzle 5 for supplying pure water as an etching protection solution for protecting the central region (device formation region) of the wafer W from the etching solution are provided. The etchant supply nozzle 4 is supplied with an etchant from an etchant supply source via an etchant supply valve 6 and an etchant supply pipe 7. The pure water supply nozzle 5 is supplied with pure water from a pure water supply source via a pure water supply valve 8.
[0026]
The etching solution supply nozzle 4 has a long shape substantially along the tangential direction of the rotation of the wafer W, and is moved by the nozzle drive mechanism 10 along the swing direction 11 substantially along the rotation radius direction of the wafer W. While being swung, it is reciprocated linearly along a reciprocating motion direction 12 along its longitudinal direction. By swinging the etchant supply nozzle 4 along the swing direction 11, the etchant supply nozzle 4 is retracted to the side of the spin chuck 1 or guided to a processing position above the peripheral edge of the wafer W. be able to. Further, the etching solution supply position to the wafer W can be changed over time by reciprocating the etching solution supply nozzle 4 along the reciprocating direction 12.
[0027]
At the time of etching processing for removing unnecessary materials on the peripheral edge of the upper surface of the wafer W, the spin chuck 1 is rotated at, for example, 200 to 1000 rpm (preferably about 300 rpm) while the wafer W is held by the spin chuck 1. Driven. At the same time, the etching solution supply nozzle 4 is guided to above the peripheral edge of the wafer W, and the etching solution supply valve 6 and the pure water supply valve 8 are opened. Further, the nozzle supply mechanism 10 causes the etching solution supply nozzle 4 to reciprocate along the reciprocating direction 12 as necessary.
[0028]
FIG. 2 is a partially enlarged perspective view for explaining the configuration of the etching solution supply nozzle 4. The etching solution supply nozzle 4 has a wafer facing surface 41 at the lower portion thereof, parallel to the wafer W and facing the upper surface of the peripheral edge of the wafer W. In the wafer facing surface 41, a plurality of discharge ports 42 are formed in a row at intervals from each other along the longitudinal direction of the etching solution supply nozzle 4, that is, the tangential direction of the rotation of the wafer W. Yes. These discharge ports 42 each discharge an etching solution 43 perpendicular to the upper surface of the wafer W. As a result, the peripheral edge of the upper surface of the wafer W is etched from the discharge port 42 toward a plurality of etching solution supply positions 46 arranged in a line at intervals on a straight line 45 crossing the peripheral edge of the wafer W. Liquid will be supplied. In this case, the plurality of etching solution supply positions 46 include those having different distances from the rotation center of the wafer W.
[0029]
FIG. 3 is a bottom view of the etching solution supply nozzle 4, showing the wafer facing surface 41 and the discharge ports 42, and the positional relationship between them and the wafer W. In this example, the plurality of discharge ports 42 are formed in a line at equal intervals. The plurality of discharge ports 42 are arranged symmetrically with respect to the rotation radius 47 of the wafer W passing through the longitudinal center position of the wafer facing surface 41. The discharge port 42 is located at an equal distance from the rotation center of the wafer W. However, the plurality of discharge ports 42 located on the rotation radius 47 and on either side thereof have different distances from the rotation center of the wafer W, and are at positions asymmetric with respect to the rotation radius 47. The distance from the rotation center of the wafer W is different between 42.
[0030]
If all the discharge ports 42 are arranged so as to be asymmetric with respect to the rotation radius 47, the distance from the rotation center of the wafer W is different for all the discharge ports 42.
Further, if the etching solution supply nozzle 4 is reciprocated along the reciprocating direction 12, the relative positional relationship between the rotation radius 47 and the etching solution supply nozzle 4 changes, and therefore the plurality of etching solution supply positions 46 change over time. As a result, the distance from the rotation center of the wafer W to them changes with time.
[0031]
FIG. 4 is an illustrative view showing a state of processing at the peripheral edge of the wafer W. FIG. Since the plurality of discharge ports 42 and the plurality of etching solution supply positions 46 corresponding to them have different distances from the rotation center of the wafer W, the peripheral edge of the wafer W has different positions with respect to the rotational radius direction of the wafer W. The etching solution 43 is supplied toward Thus, the thin film 50 formed on the surface of the wafer W is uniformly etched at each position in the rotational radius direction at the peripheral edge of the wafer W. As a result, the etching process on the peripheral edge of the wafer W can be efficiently performed, and the processing time can be shortened, so that the productivity can be significantly improved.
[0032]
From the central region of the wafer W, the pure water supplied from the pure water supply nozzle 5 flows to the peripheral portion of the wafer W by centrifugal force. However, the peripheral portion of the wafer W differs in the rotational radius direction of the wafer W. Since the etching solution 43 is formed at a plurality of positions, the liquid film 48 of the etching solution formed on the peripheral portion has a uniform concentration. For this reason, the peripheral edge of the wafer W can be efficiently etched without being greatly affected by pure water from the central region of the wafer W.
[0033]
The supply of the etching solution 43 from the discharge port 42 of the etching solution supply nozzle 4 does not have to be performed perpendicularly to the wafer W, and as shown in FIG. The etching solution 43 may be discharged in parallel to each other from the plurality of discharge ports 42 in the inclined direction.
Further, as shown in FIG. 6 (a), the etching solution supply nozzle 4 may be swung with a very small width along the swinging direction 11, as shown in FIG. 6 (b). Alternatively, the etching solution supply nozzle 4 may be reciprocally rotated around the axis 4a along the longitudinal direction within a predetermined angular range.
[0034]
  In one embodiment of the present inventionIn order to stabilize the etching solution liquid film 48 formed on the peripheral edge of the wafer W, the wafer facing surface 41 of the etching solution supply nozzle 4 is brought close to the upper surface of the wafer W as shown in FIG. Let the opposite surface 41 come into contact with the liquid film 48.TheThat is, the wafer facing surface 41 may be disposed close to the surface of the wafer W at a distance of 0.3 to 3 mm.
  In such a configuration, the liquid film 48 cannot enter the area inside the wafer W more than the inner edge 41a of the wafer facing surface 41, and the existence range of the etching liquid film 48 can be accurately controlled. . As a result, the etching processing width at the peripheral edge of the wafer W can be accurately controlled.
[0035]
As described above, when the wafer facing surface 41 is in contact with the liquid film 48, the inner edge 41 a of the wafer facing surface 41 is placed on the processing target region at the peripheral portion of the wafer W as shown in the bottom view of FIG. It is preferable to form an arc shape having a slightly larger radius of curvature than the inner peripheral edge so as to follow the inner peripheral edge. Thereby, the etching processing width can be controlled with higher accuracy.
Further, since the etching solution receives a centrifugal force on the wafer W and flows from the inner side to the outer side in the rotational radius direction, the supply amount of the etching solution is set at the rotational radius at the peripheral portion of the wafer W. The number is smaller on the inner side in the direction and larger on the outer side in the rotational radial direction. Therefore, as shown in the bottom view of FIG. 9, the discharge ports 42 may be densely arranged in the vicinity of the central portion in the longitudinal direction of the wafer facing surface 41 and roughly arranged in the vicinity of both end portions.
[0036]
  Also, FIG.Reference exampleAs shown in FIG. 4, instead of providing a plurality of discharge ports 42 on the wafer facing surface 41, one slit-shaped (slot-shaped) discharge port 42S along the longitudinal direction of the wafer facing surface 41 may be provided. Good. Also in this case, the etching solution is supplied toward a plurality of positions at substantially different distances from the rotation center of the wafer W at the peripheral portion of the wafer W. The discharge port 42S does not need to be one, and may be divided into two or more parts.
[0037]
The width of the slit-shaped discharge port 42S may be substantially uniform in the longitudinal direction or may not be uniform. For example, it may be formed wide at the center and narrow at both ends.
FIGS. 11A and 11B are bottom views showing other examples of ejection openings formed in the wafer facing surface 41. FIG. In the example of FIG. 11A, a plurality of discharge ports 42 are arranged along an arc 61 having a center of curvature at a position deviating from the rotation center of the wafer W. In this example, the arc 61 has a radius of curvature smaller than the radius of the outer peripheral edge of the wafer W.
[0038]
  On the other hand, in FIG.referenceIn the example, one slit-like discharge port 42 </ b> S formed along the similar arc 61 is provided. Even in these configurations, the etching solution can be supplied toward a plurality of positions having substantially different distances from the rotation center of the wafer W.
  FIGS. 12A and 12B are bottom views showing still another example of the discharge ports formed on the wafer facing surface 41. FIG. In the example of FIG. 12A, a plurality of (three in this example) arcs 62 each having a center of curvature at a position deviating from the rotation center of the wafer W and having a smaller radius of curvature than the outer peripheral edge of the wafer W. , 63 and 64, a plurality of discharge ports 42 are respectively arranged. In the example of FIG. 12B, a plurality of (three in this embodiment) slit-like discharge ports 42S formed along similar arcs 62, 63, and 64 are provided. Also with these configurations, the etching solution can be supplied toward a plurality of positions that are substantially different in distance from the rotation center of the wafer W.
[0039]
In the configuration of FIGS. 12A and 12B, the discharge ports 42 and 42S are provided along the arcs 62, 63, and 64 that pass through different positions with respect to the rotational radius direction, and thus the arcs 62, 63, and 64 are provided. Even if the center of curvature coincides with the rotation center of the wafer W, the etching solution can be supplied to a plurality of positions whose distances from the rotation center are substantially different.
FIGS. 13A, 13B, and 13C are bottom views showing still other examples of the discharge ports formed in the wafer facing surface 41. FIG. The example of FIG. 13A is an example in which a plurality of discharge ports 42 are staggered on the wafer facing surface 41. In other words, when a plurality of ejection ports 42 are arranged along a plurality (three in this embodiment) of parallel straight lines 65, 66, and 67 having different distances from the rotation center of the wafer W, respectively. I can say that. From another point of view, a plurality of discharge ports 42 are arranged along a plurality (11 in this embodiment) of straight lines L1 to L11 that obliquely cross the tangential direction of rotation of the wafer W. It can be said.
[0040]
In the example of FIG. 13B, a plurality of (three in this embodiment) slit-like discharge ports 42S are provided along the straight lines 65, 66, 66 as described above. In the example of FIG. 13C, a plurality (11 in this embodiment) of slit-like discharge ports 42S are provided along the straight lines L1 to L11 as described above.
Also with these configurations, the etching solution can be supplied toward a plurality of positions that are substantially different in distance from the rotation center of the wafer W.
[0041]
  14A, 14B, 14C, 14D, 14E, and 14F are bottom views showing still another example of the discharge ports formed in the wafer facing surface 41. FIG. In the example of FIG. 14 (a), a plurality of discharge ports 42 are provided along the rotational radius direction of the wafer W, as shown in FIG. 14 (b).referenceIn the example, a slit-like discharge port 42 </ b> S along the rotational radius direction of the wafer W is provided. Even in these configurations, the etching solution can be supplied to a plurality of positions having different distances from the rotation center of the wafer W.
[0042]
Further, as shown in FIG. 14 (c), a plurality of discharge port arrays including a plurality of discharge ports 42 may be provided in the longitudinal direction of the wafer facing surface 41. Further, as shown in FIG. 14D, when a plurality of discharge port arrays each including a plurality of discharge ports 42 are provided, each discharge port array is radially arranged along a plurality of rotational radius directions of the wafer W. You may arrange.
Furthermore, as shown in FIG. 14E, a plurality of slit-like discharge ports 42S may be provided along a direction orthogonal to the tangential direction of the rotation of the wafer W. Further, as shown in FIG. 14 (f), a plurality of slit-like discharge ports 42 </ b> S may be formed radially so as to be along a plurality of rotational radius directions of the wafer W, respectively.
[0043]
FIGS. 15A and 15B are bottom views for explaining the configuration of an etching solution supply nozzle 70 that can be used in place of the etching solution supply nozzle 4. The etching solution supply nozzle 70 in FIG. 15A is formed in an annular shape having an outer diameter substantially equal to the outer diameter of the wafer W, and etching is performed on the wafer facing surface 71 facing the upper surface of the wafer W in parallel. A plurality of discharge ports 72 for discharging the liquid are formed. The plurality of discharge ports 72 are formed at intervals on a plurality of straight lines 75, 76, 77, 78, 79, 80 along the tangential direction of rotation of the wafer W, and etched toward the peripheral edge of the wafer W. The liquid is supplied. Thereby, the etching solution can be supplied to the peripheral edge of the wafer W at a position substantially different from the rotation center. In the example of FIG. 15, the plurality of straight lines 75 to 80 form a polygon inscribed in the outer edge of the wafer facing surface 71 (in the example of FIG. 15, a regular hexagon).
[0044]
In the etching solution supply nozzle of FIG. 15B, the slot-like discharge ports 72S are formed on the straight lines 75 to 80 as described above. Also in this configuration, the etching solution can be supplied to the peripheral portion of the wafer W at a plurality of positions substantially different from the rotation center of the wafer W.
FIGS. 16A and 16B are bottom views showing the configuration of still another etching solution supply nozzle 90 that can be used in place of the etching solution supply nozzle 4. In the example of FIG. 16A, a plurality of discharge ports 92 for discharging an etching solution are formed at intervals along an elliptical circumference 93 on a wafer facing surface 91 that faces the upper surface of the wafer W in parallel. Has been. In the example of FIG. 16B, a plurality of slit-like ejection ports 92 </ b> S are formed on the wafer facing surface 91 along the elliptical circumference 93. Also with these configurations, the etching solution can be supplied to a plurality of positions at substantially different distances from the rotation center of the wafer W in the peripheral portion of the wafer W.
[0045]
  In the example of FIGS. 15B and 16B, a plurality of slit-like discharge ports 72S and 92S are provided, but they are connected to form one polygonal slit-like discharge port or an elliptical shape. One slit-shaped discharge port may be formed on the wafer facing surfaces 71 and 91.(Reference example).
  FIG. 17 is a bottom view of still another etching solution supply nozzle 95 that can be used in place of the etching solution supply nozzle 4. This etchant supply nozzle 95 has a plurality of discharge ports 98 arranged at intervals on a circumference 97 having a center 97a at a position deviated from the rotation center Wa of the wafer W on the wafer facing surface 96, An etching solution is supplied from the discharge port 98 to the peripheral edge of the wafer W. Also with this configuration, the etching solution can be supplied to a plurality of positions at different distances from the rotation center of the wafer W at the peripheral edge of the wafer W. In the example of FIG. 17, the radius of the circumference 97 is smaller than the radius of the outer peripheral edge of the wafer W and larger than the radius of the inner peripheral edge of the processing region at the peripheral edge of the wafer W. Since the center 97a of the periphery 97 is shifted, the radius of the periphery 97 may be equal to the radius of the inner periphery of the processing region at the periphery of the wafer W, for example.
[0046]
  Furthermore, the configuration of FIG. 17 may be modified to form a plurality of arc-shaped slit-like discharge ports along the circumference 97 on the wafer facing surface 96, or one circular slit-like shape along the circumference 97. Discharge port(Reference example)May be formed.
  It should be noted that the wafer facing surfaces 71, 91, 96 of the etching solution supply nozzles 70, 90, 95 configured as shown in FIG. 15 (a) (b), FIG. 16 (a) (b), or FIG. When contacting with the liquid film of etching solution in the vicinityIn addition,The inner edges 71a, 91a, 96a of the wafer facing surfaces 71, 91, 96 are formed so as to form a circumference having a slightly larger radius than the inner peripheral edge of the processing target area (annular area) at the peripheral edge of the wafer W. Preferably it is. In this way, the etching process width can be controlled well.
[0047]
In any of the configurations of FIGS. 11 to 17, the etching liquid is discharged in a direction parallel to each other from the plurality of discharge ports 42, 72, 92, 98 or the slit-shaped discharge ports 42 S, 72 S, 92 S. The direction is perpendicular to the surface of the wafer W or inclined toward the outer side in the rotational radius direction of the wafer W. Therefore, the etching solution supply position at the peripheral edge of the wafer W follows the arrangement or shape of the discharge ports 42, 72, 92, 98, 42S, 72S, 92S.
[0048]
Of course, as long as the etching solution can be supplied to a plurality of positions at substantially different distances from the rotation center of the wafer W at the peripheral edge of the wafer W, the plurality of discharge ports 42, 72, 92, 98 or the plurality of slit-like discharges. The directions of the etching liquid discharged from the outlets 42S, 72S, and 92S do not need to be parallel to each other.
1 to 17, the etchant from the plurality of discharge ports 42, 72, 92, 98 or the plurality of slit-like discharge ports 42S, 72S, 92S formed at intervals is transferred to the wafer. The etching solution supply positions reaching the surface of the peripheral edge of W are adjacent to each other sufficiently close to each other so that the liquid films formed by the etching solution supplied to the adjacent etching solution supply positions are combined with each other. It has become.
[0049]
  As mentioned above, although several embodiment of this invention was described, this invention can also be implemented with another form..
[0050]
  For exampleIn the above embodiment, the suction type spin chuck 1 that sucks and holds the central portion of the lower surface of the wafer W is used. However, a mechanical chuck having a configuration in which the peripheral end surface of the wafer W is held by chuck pins is used. May be.
  Further, the substrate to be processed is not limited to a semiconductor wafer, but may be another circular substrate such as an optical disk substrate, a magneto-optical disk substrate, and a magnetic disk substrate, or a square substrate such as a glass substrate for a liquid crystal display device. There may be.
[0051]
In addition, various design changes can be made within the scope of matters described in the claims.
[Brief description of the drawings]
FIG. 1 is a perspective view schematically showing a configuration of a substrate peripheral edge processing apparatus according to an embodiment of the present invention.
FIG. 2 is a partially enlarged perspective view for explaining the configuration of an etching solution supply nozzle.
FIG. 3 is a bottom view of an etching solution supply nozzle.
FIG. 4 is an illustrative view showing a state of processing at a peripheral portion of a wafer.
FIG. 5 is an illustrative view showing an example in which an etching solution is supplied along a direction inclined with respect to a wafer.
FIG. 6 is an illustrative view showing an example of swinging or rotating an etching solution supply nozzle.
FIG. 7 is a schematic cross-sectional view showing an example in which the wafer facing surface of the etching solution supply nozzle is brought into contact with the etching solution liquid film on the wafer.
FIG. 8 is a bottom view showing a configuration example of an etching solution supply nozzle suitable for bringing the wafer facing surface into contact with a liquid film of an etching solution on the wafer.
FIG. 9 is a bottom view showing an example in which discharge ports are arranged densely on the wafer facing surface.
FIG. 10 is a bottom view showing an example in which slit-shaped ejection openings are formed on the wafer facing surface.
FIG. 11 is a bottom view showing another example of ejection openings formed on the wafer facing surface.
FIG. 12 is a bottom view showing still another example of the discharge ports formed on the wafer facing surface.
FIG. 13 is a bottom view showing still another example of the discharge ports formed on the wafer facing surface.
FIG. 14 is a bottom view showing still another example of the discharge ports formed on the wafer facing surface.
FIG. 15 is a bottom view showing another configuration example of the etching solution supply nozzle.
FIG. 16 is a bottom view showing still another configuration example of the etching solution supply nozzle.
FIG. 17 is a bottom view showing still another configuration example of the etching solution supply nozzle.
FIG. 18 is a schematic cross-sectional view for explaining a problem of a conventional substrate peripheral edge processing apparatus.
[Explanation of symbols]
1 Spin chuck
1a Vertical axis
2 Rotating shaft
3 Rotation drive mechanism
4 Etching solution supply nozzle
5 Pure water supply nozzle
6 Etching solution supply valve
7 Etching solution supply piping
8 Pure water supply valve
10 Nozzle drive mechanism
11 Swing direction
12 Reciprocating direction
41 Wafer facing surface
41a Inner edge
42 Discharge port
42S slit outlet
43 Etching solution
46 Etch solution supply position
48 liquid film
50 thin film
70 Etching solution supply nozzle
71 Wafer facing surface
71a Inner edge
72 Discharge port
72S slit outlet
90 Etching solution supply nozzle
91 Wafer facing surface
92 Discharge port
92S slit outlet
95 Etching solution supply nozzle
96 Wafer facing surface
98 Discharge port
W wafer
Wa center of rotation

Claims (12)

A substrate peripheral processing apparatus for supplying an etchant to a peripheral portion of a substrate and etching away unnecessary materials on the peripheral portion,
Substrate rotating means for rotating the substrate about a rotation axis that passes through substantially the center of the substrate and is substantially orthogonal to the substrate surface;
At the periphery of the substrate, a nozzle body having a plurality of discharge port for supplying an etching liquid of the same type to a plurality of positions where the distance is different from the axis of rotation of the substrate,
On the surface of the substrate, an etching protection liquid supply for supplying an etching protection liquid toward an inner position from a supply position closest to the rotation axis among etching liquid supply positions from the plurality of discharge ports of the nozzle body. and means only including,
The nozzle body has a substrate facing surface facing the surface of the substrate, and the plurality of discharge ports are opened on the substrate facing surface,
The substrate facing surface is disposed close to the substrate so as to contact an etching solution supplied to the peripheral portion of the substrate and form a liquid film between the substrate facing surface and the peripheral portion of the substrate. the substrate peripheral edge processing apparatus according to claim <br/> that it is. Inner edge of the substrate facing surface, that the substrate peripheral edge processing apparatus according to claim 1, wherein are formed in an arc shape along the inner peripheral edge of the processing target area of the peripheral portion of the substrate. Said substrate-facing surface is formed along the tangential direction of the rotation direction of the substrate, the discharge port of the upper Kifuku number is densely arranged in the vicinity of the tangential direction central portion of the substrate-facing surface in the vicinity of the end portion 3. The substrate peripheral edge processing apparatus according to claim 1 , wherein the substrate peripheral edge processing apparatus is arranged roughly. The plurality of discharge ports, the substrate peripheral edge according to any one of 3 claims 1, characterized in that to a plurality of positions substantially aligned on a straight line at the periphery of the substrate and supplies an etchant Processing equipment. The plurality of discharge ports supply an etching solution toward a plurality of positions arranged on an arc having a center of curvature at a position deviated from the rotation center of the substrate at a peripheral portion of the substrate. It claims 1 to to the substrate peripheral edge processing apparatus according to any one of 3. The plurality of discharge ports, the substrate peripheral edge processing apparatus according to any one of claims 1 to 5, characterized in that it has a discharge opening which opens in a slit shape. The plurality of discharge ports supply an etching solution toward a plurality of positions arranged so as to surround the rotation axis of the substrate at a peripheral portion of the substrate. 7. The substrate peripheral edge processing apparatus according to any one of claims 6 to 6 . 8. The substrate peripheral edge processing apparatus according to claim 7 , wherein the plurality of discharge ports supply an etching solution toward a plurality of positions arranged along each side of the polygon. 8. The substrate peripheral processing apparatus according to claim 7 , wherein the plurality of discharge ports supply an etching solution toward a plurality of positions arranged along an elliptical circumference. The plurality of discharge ports, claim, characterized in that to supply an etching liquid toward a plurality of positions disposed along the circumference around the differences from the rotational center of the substrate 7 The substrate peripheral edge processing apparatus as described. The plurality of discharge ports supply an etching solution to a peripheral edge portion of the substrate along a direction perpendicular to the substrate or a direction inclined toward the outside of the substrate. Item 11. A substrate peripheral edge processing apparatus according to any one of Items 1 to 10 . A substrate peripheral processing method of supplying an etching solution to a peripheral portion of a substrate and etching away unnecessary materials on the peripheral portion,
A substrate rotation step of rotating the substrate about a rotation axis that passes through substantially the center of the substrate and is substantially orthogonal to the substrate surface;
During this substrate rotating step, at the periphery of the substrate, a nozzle body having a plurality of discharge ports, the etching liquid supplying etching liquid of the same type to a plurality of positions where the distance is different from the axis of rotation of the substrate A supply process;
Etching protection that supplies an etching protection liquid toward a position inward of a supply position closest to the rotation axis among a plurality of positions to which the etching liquid is supplied on the substrate surface during the substrate rotation process. only contains a liquid supply step,
The nozzle body has a substrate facing surface facing the surface of the substrate, and the plurality of discharge ports are opened on the substrate facing surface,
In the etching solution supply step, the substrate facing surface is brought into contact with the etching solution supplied to the peripheral portion of the substrate, and a liquid film is formed between the substrate facing surface and the peripheral portion of the substrate. A substrate peripheral edge processing method , comprising a step of disposing the substrate-resistant surface opposite to the substrate.

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