JPWO2011114883A1 - Resist pattern forming apparatus, resist pattern forming method, and wafer lens manufacturing method - Google Patents

Abstract

Provided is a resist pattern forming apparatus capable of suppressing a necessary resist pattern from being removed or partially lost. The resist pattern forming apparatus 70 includes a rotatable stage 72 on which a substrate is disposed, a developer discharge unit 78 that discharges developer to the substrate disposed on the stage 72, and the substrate disposed on the stage 72. Gas ejecting section 80 for ejecting gas, and when the substrate is placed on the stage 72 and the developer is ejected from the developer ejecting section 78 to the peripheral edge of the substrate, the gas ejecting section 80. The gas is ejected from the substrate, and the gas flows from the inside of the substrate toward the peripheral portion.

Description

  The present invention relates to a resist pattern forming apparatus, a resist pattern forming method, and a wafer lens manufacturing method.

  Conventionally, a spin coating method using a spin coater or the like is generally used as a technique for uniformly forming a desired resist pattern on a wafer. In this method, due to the characteristics of the spin coater, the resist applied by the spin coater is subjected to centrifugal force on the portion formed outside the region where the desired resist pattern necessary for the wafer is originally formed from the center of rotation, that is, the peripheral edge of the wafer. If the resist is applied with a particularly large thickness due to the action of the resist, and then the resist is exposed and developed using a predetermined mask pattern and developer, a residue (residue) of the resist is generated at the peripheral edge of the wafer. End up. The resist remaining on the peripheral edge of the wafer may peel off from the wafer when handling the wafer, causing dust generation.

  For this reason, in order to remove the resist on the peripheral edge of the wafer, a process called “edge rinse” in which a developer is intensively discharged to the peripheral edge of the wafer is known (see, for example, Patent Documents 1 and 2). In Patent Document 1, ozone water is used as a cleaning liquid for edge rinsing to achieve clean cleaning. In Patent Document 2, a positive resist whose exposed portion is soluble in a developer is used, and development is performed while exposing light to the peripheral resist specifically (or development after exposure), which is unnecessary. The resist is removed.

JP 2002-208550 A JP 2001-68393 A

  However, when edge rinsing is performed, the developer is excessively scattered on the resist pattern near the periphery of the wafer, and even the necessary resist pattern is removed, or the resist pattern is partially damaged. Resulting in.

  Such a problem has occurred not only in the case of semiconductor manufacturing but also in the case of manufacturing a wafer lens in which a plurality of resin lenses are formed on a wafer-like glass substrate in recent years.

  That is, in the production of a wafer lens, there is a case where a diaphragm is formed between the glass substrate and the resin lens portion, and this diaphragm is constituted by a resist pattern as described above. In the glass substrate constituting the wafer, a pattern region as a desired diaphragm is formed in a portion where the lens portion is to be formed, but a portion formed outside the region as viewed from the center of rotation, that is, an end portion of the substrate In some cases, the aperture pattern formed at a position close to the peripheral edge located between the two is removed more than necessary or partially lost.

  Furthermore, in addition to the diaphragm near the periphery, for example, a resin lens part is prepared with a molding die having a plurality of molding surfaces corresponding to the shape of the lens part, and a resin is formed between the glass substrate to be formed. Is formed by pressing the resin between the mold and the glass substrate and curing it with light or heat energy. In this case, the alignment between the mold and the glass substrate or these resins are formed. When forming the lens part on both sides of the glass substrate, the alignment mark should be the same for positioning the mold on both sides so that the lens part does not shift the optical axis of the corresponding lens part on the front and back sides. In many cases, the alignment mark is removed or partially lost.

  Therefore, a main object of the present invention is to provide a resist pattern forming apparatus, a resist pattern forming method, and a wafer lens manufacturing method capable of suppressing a necessary resist pattern from being removed or partially lost. There is.

According to one aspect of the invention,
In a resist pattern forming apparatus for forming a resist pattern on a substrate,
A rotatable stage on which the substrate is disposed;
A developer discharge section for discharging developer to the substrate disposed on the stage;
A gas ejection portion for ejecting gas to the substrate disposed on the stage,
When the substrate is placed on the stage and the developer is discharged from the developer discharge portion to the peripheral portion of the substrate, the gas from the gas ejection portion is transferred from the inside of the substrate to the peripheral portion of the substrate. The resist pattern forming apparatus is characterized in that gas is ejected from the gas ejection portion.

According to another aspect of the invention,
In a resist pattern forming method for forming a resist pattern on a substrate,
A resist coating step of applying a resist to the substrate while rotating the substrate;
An exposure step of exposing the resist on the substrate through a mask pattern having a predetermined shape;
A development step of discharging a developer to the resist after exposure;
An edge rinsing process for cleaning the peripheral edge of the substrate;
A cleaning step for washing away the developer on the substrate;
A drying step of drying the substrate,
In the edge rinsing step, a resist pattern forming method is provided in which a developer is discharged to the peripheral edge of the substrate while flowing a gas from the inside of the substrate toward the peripheral edge.

According to another aspect of the invention,
A method for producing a wafer lens, comprising a diaphragm having a plurality of openings on a surface of a glass substrate, and a plurality of resin lens parts provided corresponding to the openings of the diaphragm,
Forming a resist layer over substantially the entire surface of the glass substrate;
An exposure step of exposing a resist layer formed on the glass substrate through a predetermined mask pattern for forming the aperture;
A development step of developing the resist layer after the exposure step with a developer;
An edge rinsing step for cleaning a peripheral portion located between a region of the surface of the glass substrate where the resist layer of the predetermined mask pattern is formed and an end of the glass substrate;
A washing step for washing the developer after the developing step;
A drying step of drying the glass substrate after the cleaning step;
After the drying step, forming a plurality of resin lens portions on the surface of the glass substrate on which the diaphragm is formed,
In the edge rinsing step, a developing solution is discharged to the peripheral edge of the surface of the glass substrate, and a gas is allowed to flow from the inside to the peripheral edge of the glass substrate. .

  According to the present invention, during edge rinsing, gas flows from the inside to the outside of the substrate, so that it is possible to prevent the developer from splashing back and scattering toward the inside of the substrate, which is necessary. The resist pattern can be prevented from being removed or partially lost.

It is a perspective view which shows schematic structure of a wafer lens. FIG. 2 is an exploded cross-sectional view taken along the line II in FIG. 1. It is a top view which shows roughly the surface (aperture pattern etc.) of the glass substrate of a wafer lens. It is (a) side view (b) top view which shows schematic structure of an aperture forming apparatus. 6 is a diagram for schematically explaining the discharge angle of the developer in the developer discharge section. It is a flowchart which shows the process of an aperture forming method roughly. It is drawing which shows the modification of the aperture forming apparatus of FIG.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 2, the wafer lens 52 has a wafer-like glass substrate 16. The glass substrate 16 is an example of a substrate. On the glass substrate 16, a diaphragm 18 having a plurality of openings 18 a is formed in a desired region including a central portion that is a part of the glass substrate 16. A resin part 20 having a resin lens part (convex lens part 20a, concave lens part 24a) as a part is formed on the glass substrate 16 at a position corresponding to the opening 18a. The resin portion 20 is formed in a region where the diaphragm 18 is formed from the central portion of the glass substrate 16.

  As shown in FIG. 3, the diaphragm 18 is divided into individual pieces corresponding to the lens portions (convex lens portion 20a, concave lens portion 24a) and has a rectangular shape, and a circular opening 18a is formed at the center thereof. Is formed. However, the diaphragm 18 is not limited to such an individual piece, but may be formed on one surface of the glass substrate 16 and formed with a plurality of openings 18a.

  The ID recording part 58 is formed in the peripheral part of the diaphragm 18.

  The glass substrate 16 has two regions 64 and 66 where the diaphragm 18 is not formed. In each of the regions 64 and 66, one cross-shaped alignment mark 64a and 66a is formed. The alignment marks 64a and 66a are used for alignment with other members, for example, when they are laminated with other wafer lenses.

  The diaphragm 18 and the alignment marks 64a and 66a are made of the same material, and specifically are made of a light-shielding photoresist. As the light shielding photoresist, a photoresist mixed with carbon black is applied.

  The ID recording unit 58 is configured by a two-dimensional barcode, and the wafer lens 52 can be distinguished from other wafer lenses.

  As shown in FIG. 2, the diaphragm 18 and the ID recording portion 58 are covered with the resin portion 20.

  The resin portion 20 is formed on the surface of the glass substrate 16 on which the diaphragm 18 and the ID recording portion 58 are formed, and constitutes a convex lens portion 20a and a non-lens portion 20b.

  A diaphragm 22 and a resin portion 24 are formed below the glass substrate 16.

  The diaphragm 22 is formed in the lower part of the glass substrate 16 in the same pattern (see FIG. 3) as that formed in the upper part of the glass substrate 16. The diaphragm 22 is also made of a light shielding photoresist similar to the diaphragm 18, the ID recording portion 58, and the alignment marks 64a and 66a.

  The diaphragm 22 is covered with a resin portion 24.

  The resin part 24 constitutes a concave lens part 24a at a position coaxial with the convex lens part 20a.

  A portion constituted by one set of convex lens portion 20a, diaphragm 18, diaphragm 22, and concave lens portion 24a corresponds to one unit of a component, and a large number of these are held on the glass substrate 16 with other wafer lenses and spacer substrates. Laminated.

  In such a wafer lens laminate, in order from the upper side to the lower side in FIG. 2, each lens of the convex lens portion 20a, the aperture 18a of the aperture 18, the aperture 22a of the aperture 22, the concave lens 24a, and other wafer lenses. And the opening of the spacer substrate are arranged on the optical axis 34 and cut together along the dicing line 61 to form a lens unit.

  Subsequently, a resist pattern forming apparatus will be described.

  As shown in FIG. 4, the resist pattern forming apparatus 70 has a circular stage 72. The stage 72 has substantially the same size as the glass substrate 16 and can adsorb and fix the glass substrate 16 by a vacuum chuck mechanism. A support body 74 and a rotating shaft 76 that support the stage 72 are connected to the lower portion of the stage 72. The rotating shaft 76 is connected to a motor (not shown). When the rotating shaft 76 is rotated by receiving the rotational force of the motor, the support 74 is rotated accordingly, and the stage 72 is rotated in a predetermined direction (see the arrow in FIG. 4B).

  Above the stage 72, a developer discharge unit 78 that discharges the developer and a gas ejection unit 80 that ejects gas are provided.

  The developer discharge part 78 is movable between the center part and the peripheral part above the stage 72 (see the dotted line part and the arrow in FIG. 4A). The peripheral edge is the glass substrate 16 on the outer side of the outermost portion of the aperture pattern (18) made of a desired resist or the portion where the alignment marks (64a, 66a) are formed on the glass substrate 16 to be arranged. It is the site | part located between the edge parts. As shown in FIG. 4A, the developer discharge unit 78 is arranged in a direction orthogonal to the stage 72 when arranged at the center of the stage 72, and on the other hand, when arranged at the peripheral portion of the stage 72, It arrange | positions in the state inclined in the direction which goes to a peripheral part from the center part of the stage 72. FIG. As shown in FIG. 5, the developer discharge angle of the developer discharge portion 78 is variable, and the development is performed at an angle α (°) with respect to the parallel line L1 in the discharge direction passing through each end portion as well as both ends of the discharge port. It is possible to discharge the developer, and it is also possible to discharge the developer at an angle β (°) which is a narrow angle by θ (°).

  As shown in FIG. 4, the gas ejection part 80 is disposed in the vicinity of the developer discharge part 78 located above the stage 72 and on the peripheral edge side of the stage 72. In a state where the glass substrate 16 is installed on the stage 72, the gas ejection part 80 is disposed on the position side corresponding to the peripheral part of the glass substrate 16. An inert gas such as nitrogen gas or argon gas is ejected from the gas ejection part 80. The inert gas is an example of a fluid, and other gases may be ejected.

  Next, a method for manufacturing the wafer lens 52 centering on the resist pattern forming method will be described.

  Here, the glass substrate 16 is used as an example of the substrate, and the diaphragm 18, the ID recording portion 58, and the alignment marks 64a and 66a are formed as an example of the resist pattern.

As shown in FIG. 6, the wafer lens 52 is mainly manufactured through the steps (S1) to (S7).
(S1) A resist is applied to the glass substrate 16.
(S2) The resist is exposed through a mask pattern having a predetermined shape.
(S3) The resist after exposure is developed as a whole.
(S4) The resist on the peripheral edge of the glass substrate 16 is locally developed, that is, edge rinsed.
(S5) The glass substrate 16 after development is washed.
(S6) The glass substrate 16 after washing is dried.
(S7) The glass substrate 16 after drying is fired.

  In the step (S1), a light-shielding photoresist is dropped onto the glass substrate 16 while rotating the glass substrate 16 using a known spin coater, and the light-shielding photoresist (resist layer) is applied to almost the entire surface of the glass substrate 16. Apply.

  In the step (S2), a mask having a predetermined shape corresponding to the shape of the diaphragm 18 or the like is placed above the surface of the glass substrate 16, and light such as ultraviolet light is exposed toward the glass substrate 16 from above.

  In the step (S 3), the exposed glass substrate 16 is placed on the stage 72 of the aperture forming apparatus 70, and the developer discharge unit 78 is placed in the center above the stage 72. Thereafter, the stage 72 is rotated to rotate the glass substrate 16, and together with this, the developer is widely discharged from the developer discharge portion 78 toward the glass substrate 16 at an angle α. As the glass substrate 16 rotates, the developer spreads from the central portion toward the peripheral portion, and the light-shielding resist after exposure is developed over the entire surface of the glass substrate 16. Here, the exposed light-shielding resist is removed.

  In the step (S4), the developer discharge part 78 is moved from the central part above the stage 72 to the peripheral part, and the developer is again supplied from the developer discharge part 78 at the peripheral part above the stage 72. Discharge toward At the same time, gas is ejected from the gas ejection part 80 toward the glass substrate 16, and the gas flows so that the gas hits the outside (periphery part) from the inside (rotation center) of the glass substrate 16 (FIG. 4 ( b)). That is, in the step (S4), the developing solution is specifically discharged while flowing gas to the peripheral edge of the glass substrate 16.

  In this case, the developer discharge angle of the developer discharge portion 78 is set to be an angle β, which is narrower than the developer discharge angle in the step (S3), and the discharge range of the developer toward the peripheral edge of the glass substrate 16 is specified. .

  Note that the direction (arrangement) of the developer discharge section 78 and the discharge direction of the developer at the peripheral edge above the stage 72 can be changed according to the situation such as the residue of the light-shielding resist. For example, at the peripheral edge above the stage 72, as shown in FIG. 4B, the direction of the developer discharge unit 78 is changed, and the developer is discharged in a direction along the rotation direction of the stage 72 (forward direction). Alternatively, the developer may be discharged in a direction opposite to the rotation direction of the stage 72 (reverse direction). However, if the developer is discharged in the reverse direction, it will repel the rotation of the glass substrate 16 on the stage 72 and the developer may bounce off and scatter, so the discharge direction of the developer is preferably the forward direction. It is good to do.

  In the step (S4), gas is ejected from the gas ejection part 80 in the vicinity of the developer discharge part 78 simultaneously with the development of the light-shielding resist at the peripheral part of the glass substrate 16, so It is possible to suppress the inward movement or the scattering of the developing solution and adhere to the glass substrate 16, and only the light-shielding resist on the peripheral edge of the glass substrate 16 is developed (removed) in a concentrated manner. It is possible.

  In addition, when the discharge position of the developing solution to the peripheral part of the glass substrate 16 greatly deviates from a desired position due to the gas jetting by the gas jetting part 80, it is possible to cope with it by adjusting the gas jetting pressure. is there.

  In the step (S5), a cleaning liquid such as ultrapure water is jetted onto the glass substrate 16 to wash away the developer on the glass substrate 16, and the developed glass substrate 16 is cleaned.

  In the step (S6), the glass substrate 16 is dried by applying hot air to the cleaned glass substrate 16 or by transferring the cleaned glass substrate 16 to a thermostatic bath. As a result, the diaphragm 18, the ID recording portion 58, and the alignment marks 64a and 66a having a predetermined pattern can be formed on the glass substrate 16. Even when the aperture 22 is formed, the same steps as (S1) to (S6) may be repeated on the back surface of the glass substrate 16.

  In addition, the process of the process of (S4) may be implemented after the process of (S5), and may be implemented after the process of (S6).

  In the step (S7), the dried glass substrate 16 is baked to completely cure the light-shielding resist (resin) constituting the diaphragm 18, the diaphragm 22, the ID recording portion 58, and the alignment marks 64a and 66a.

  After that, the mold is positioned with reference to the alignment marks 64a and 66a of the glass substrate 16, the resin is filled between the glass substrate 16 and the mold, the resin is cured, and the mold is released. A wafer lens 52 having 20 and 24 can be manufactured.

  According to the present embodiment described above, in the edge rinsing step (S4), gas is ejected from the gas ejection portion 80 and gas is allowed to flow from the inside to the outside of the glass substrate 16, so that the developer is the glass substrate 16. Can be prevented from bouncing or scattering toward the inside, and necessary resist patterns (aperture 18, ID recording portion 58, alignment marks 64a, 66a) are removed or partially lost. Can be suppressed.

  As shown in FIG. 7, the developer discharge section (78) may be constituted by two developer discharge sections 78a and 78b. Specifically, above the stage 72, the developer discharge portion 78 a is disposed at the center of the stage 72, and the developer discharge portion 78 b is disposed at the periphery of the stage 72. At this time, the gas ejection part 80 is disposed in the vicinity of the developer discharge part 78b. In a state in which the glass substrate 16 is installed on the stage 72, the gas ejection part 78 is disposed on the developer discharge part 78 b side from a position corresponding to the center part of the glass substrate 16. The developer discharge unit 78a discharges the developer at an angle α, and the developer discharge unit 78b discharges the developer at an angle β. In this configuration, the developer may be discharged from the developer discharge portion 78a in the step (S3), and the developer may be discharged from the developer discharge portion 78b in the step (S4).

16 glass substrate 18 aperture 18a opening 20 resin portion 20a convex lens portion 20b non-lens portion 22 aperture 24 resin portion 24a concave lens portion 52 wafer lens 58 ID recording portion 64, 66 region 64a, 66a alignment mark 70 resist pattern forming device 72 stage 74 Support body 76 Rotating shaft 78 Developer discharge part 78a, 78b Developer discharge part 80 Gas ejection part

Claims (16)

In a resist pattern forming apparatus for forming a resist pattern on a substrate,
A rotatable stage on which the substrate is disposed;
A developer discharge section for discharging developer to the substrate disposed on the stage;
A gas ejection portion for ejecting gas to the substrate disposed on the stage,
When the substrate is placed on the stage and the developer is discharged from the developer discharge portion to the peripheral portion of the substrate, the gas from the gas ejection portion is transferred from the inside of the substrate to the peripheral portion of the substrate. The resist pattern forming apparatus is characterized in that a gas is ejected from the gas ejecting portion so as to hit. The resist pattern forming apparatus according to claim 1,
The resist pattern forming apparatus, wherein a developer discharge direction of the developer discharge portion is a forward direction with respect to a rotation direction of the substrate. The resist pattern forming apparatus according to claim 1,
The resist pattern forming apparatus, wherein a developer discharge direction of the developer discharge section is opposite to a rotation direction of the substrate. In the resist pattern forming apparatus according to any one of claims 1 to 3,
The developer discharge part is movable between a central part and a peripheral part of the substrate disposed on the stage;
An apparatus for forming a resist pattern, wherein the developer is discharged at an angle narrower than a discharge angle of the developer when positioned at the central portion of the substrate when positioned at the peripheral edge of the substrate. The resist pattern forming apparatus according to claim 4,
The resist pattern forming apparatus, wherein the gas ejection part is arranged on a peripheral edge side of the substrate on which the developer discharge part moves. In the resist pattern forming apparatus according to any one of claims 1 to 3,
The developer discharge part
A first discharge unit disposed at a central portion of the substrate disposed on the stage and discharging a developer at a first discharge angle;
A resist pattern forming apparatus, comprising: a second discharge section that is disposed on a peripheral edge side of the substrate disposed on the stage and discharges the developer at an angle smaller than the first discharge angle. The resist pattern forming apparatus according to claim 6,
The resist pattern forming apparatus, wherein the gas jetting part is arranged on the second ejection part side arranged on the peripheral edge side of the substrate. In the resist pattern formation apparatus as described in any one of Claims 1-7,
A resist pattern forming apparatus, wherein the resist pattern is a diaphragm or an alignment mark for a wafer lens. In a resist pattern forming method for forming a resist pattern on a substrate,
A resist coating step of applying a resist to the substrate while rotating the substrate;
An exposure step of exposing the resist on the substrate through a mask pattern having a predetermined shape;
A development step of discharging a developer to the resist after exposure;
An edge rinsing process for cleaning the peripheral edge of the substrate;
A cleaning step for washing away the developer on the substrate;
A drying step of drying the substrate,
In the edge rinse step, a developing solution is discharged to the peripheral edge of the substrate while flowing a gas from the inside to the peripheral edge of the substrate. In the resist pattern formation method of Claim 9,
A resist pattern forming method, wherein the edge rinse process is performed between the developing process and the cleaning process. In the resist pattern formation method of Claim 9,
The resist pattern forming method, wherein the edge rinse process is performed between the cleaning process and the drying process. In the resist pattern formation method of Claim 9,
A resist pattern forming method, wherein the edge rinse process is performed after the drying process. A method for producing a wafer lens, comprising a diaphragm having a plurality of openings on a surface of a glass substrate, and a plurality of resin lens parts provided corresponding to the openings of the diaphragm,
Forming a resist layer over substantially the entire surface of the glass substrate;
An exposure step of exposing a resist layer formed on the glass substrate through a predetermined mask pattern for forming the aperture;
A development step of developing the resist layer after the exposure step with a developer;
An edge rinsing step for cleaning a peripheral portion located between a region of the surface of the glass substrate where the resist layer of the predetermined mask pattern is formed and an end of the glass substrate;
A washing step for washing the developer after the developing step;
A drying step of drying the glass substrate after the cleaning step;
After the drying step, forming a plurality of resin lens portions on the surface of the glass substrate on which the diaphragm is formed;
Have
In the edge rinsing step, a developer is discharged to the peripheral portion of the surface of the glass substrate, and a gas is allowed to flow from the inside of the glass substrate toward the peripheral portion. In the manufacturing method of the wafer lens according to claim 13,
A wafer lens manufacturing method, wherein the edge rinse process is performed between the developing process and the cleaning process. In the manufacturing method of the wafer lens according to claim 13,
A wafer lens manufacturing method, wherein the edge rinse process is performed between the cleaning process and the drying process. In the manufacturing method of the wafer lens according to claim 13,
A method of manufacturing a wafer lens, wherein the edge rinse process is performed after the drying process.