JP4927024B2 - Microlens formation method, alignment mark optimization method, solid-state imaging device manufacturing method, and electronic information device - Google Patents

Description

  The present invention relates to a method for forming a microlens, a method for manufacturing a solid-state imaging device, and an electronic information device, and more particularly, a method for forming a microlens that constitutes a solid-state imaging device, and a solid-state imaging device using the method for forming a microlens. The present invention relates to a manufacturing method and electronic information equipment using the solid-state imaging device obtained by the manufacturing method of the solid-state imaging device.

  2. Description of the Related Art Conventionally, some solid-state imaging devices include microlenses arranged on the light-receiving portions of each pixel so that incident light is efficiently collected on the light-receiving portions. The manufacturing method will be briefly described.

  FIG. 9 is a diagram for explaining such a conventional method for manufacturing a solid-state imaging device, and FIGS. 9A to 9C show the microlens formation steps in the order of processing.

  First, a pixel portion (not shown) in which a plurality of pixels are arranged on the surface region of the semiconductor substrate 1 and a peripheral circuit (a diagram) that drives the pixel portion and processes a pixel signal from the pixel portion. Further, a planarizing film 2 is formed on the entire surface, and a photosensitive thermoplastic resin is applied on the planarizing film 2 to form a lens material layer Pr. Subsequently, the lens material layer Pr is selectively exposed with the exposure light L using an exposure mask (reticle) Rc (FIG. 9A). This exposure mask Rc is formed by forming a light shielding film Rc2 made of chromium or the like having a predetermined pattern on the surface of a transparent substrate Rc1 such as glass. The exposed part (exposed part) Pr2 of the lens material layer Pr is a part that dissolves in the developer, and the unexposed part (non-exposed part) Pr1 of the lens material layer Pr is a part that does not dissolve in the developer. It is.

  Next, the lens material layer Pr is developed to selectively remove the exposed portion Pr2 of the lens material layer Pr, leaving only the unexposed portion Pr1 on the planarizing film 2 (FIG. 9B). .

  Thereafter, the microlens M is formed by processing the non-exposed portion Pr1 of the lens material layer Pr into a lens shape by heating and melting (FIG. 9C).

  FIG. 10 is a view for explaining an exposure apparatus used for exposure of the lens material layer, and shows a schematic configuration thereof.

  The exposure apparatus 110 includes a wafer stage 112 on which a wafer Wf is placed, a support base 111 that supports the wafer stage 112 so as to be movable in the horizontal direction, and an exposure light source 114 that generates exposure light L. . The exposure apparatus 110 includes a reticle alignment unit 116 that supports the reticle Rc and aligns the reticle Rc with respect to the support base 111, and a stage drive unit 115 that moves the stage 112 with respect to the support base 111. Have. The exposure apparatus 110 condenses the exposure light emitted from the exposure light source 114 and passed through the reticle onto the wafer Wf, and reflects the light Lr from the surface of the wafer Wf, and is reflected by the optical system 113. And a control unit 117 for controlling the reticle alignment unit 116 and the support driving unit 115 based on the light from the wafer surface.

  FIG. 11 is a view for explaining a method of performing an exposure process on the photosensitive material layer formed on the wafer using the exposure apparatus 110.

  The wafer Wf shown in FIG. 11 is a first half step of manufacturing a solid-state imaging device, in which the pixel portion and the peripheral circuit portion are formed in each chip region 100. A reticle Rc shown in FIG. 11 has an exposure pattern for nine chip regions arranged in a matrix of 3 rows and 3 columns.

  When such a wafer Wf is placed on the wafer stage 112 of the exposure apparatus 110, the exposure apparatus 110 aligns the wafer Wf and the reticle Rc by the reticle alignment unit 116 and the stage drive unit 115. Thereafter, the wafer is sequentially exposed every 9 chips.

  By the way, in the solid-state imaging device provided with such a microlens, the distance between adjacent microlenses can be reduced to increase the light collection rate and improve the sensitivity. However, in the above-described microlens formation method, Since all the microlenses are formed simultaneously, there are the following problems.

  That is, there is a limit to the resolution of the photolithography technique, and when patterning the lens material layer with a patterning dimension less than the resolution, it is very difficult to reliably form a desired dimension pattern. Further, when the distance between the patterned lens material layers becomes narrow, the adjacent lens material layers melted by the heat treatment come into contact with each other, so that the surface shape of the portion where the adjacent microlens contacts becomes one continuous curved surface shape. There is a risk that a defectively shaped microlens may be formed. Therefore, it is difficult to reduce the interval between the microlenses while maintaining the convex lens shape of the microlenses.

  Therefore, as disclosed in the following Patent Documents 1 to 8, a method for forming a microlens in two steps has been proposed.

  In these microlens forming methods disclosed in the literature, a microlens is formed on a pixel array in which a plurality of pixels are arranged in a matrix, and a pixel region where a microlens is formed and a pixel region where a microlens is not formed. The method includes a first microlens process that is selectively formed so as to form a checkered lattice shape, and a second microlens formation process that forms a microlens in the remaining pixel region of the pixel array.

  Thus, by dividing the process of forming the microlens on the pixel array into two processes, the occurrence of a lens non-formation area on the pixel array can be suppressed without causing the adjacent microlens to be fused. . Thereby, the lens non-formation area | region between microlenses can be minimized, and the solid-state imaging device which improved the condensing efficiency can be obtained.

  Hereinafter, a method for forming the microlens in two steps will be described.

  In this case, in the first microlens process and the second microlens process, the exposure mask (reticle) is aligned with the wafer by using predetermined alignment marks formed on the wafer.

  FIG. 12 is an enlarged view of the surface area of the wafer Wf shown in FIG. 11, and each chip is cut out from the area (chip area) Rc in which the solid-state imaging element chip (solid-state imaging device) is formed and the wafer Wf. The scribe areas SLh and SLv that are cut at the time are enlarged.

  The wafer Wf shown in FIG. 12 is in a stage where the first half of the process of forming circuit elements and wirings has been completed. That is, on the wafer Wf, chip regions Rc in which solid-state image sensor chips are to be formed are arranged in a matrix, and each chip region Rc has a pixel array Ap composed of a plurality of pixels Px created in the first half process. And a peripheral circuit (not shown) located around the pixel array Ap.

  An area between adjacent chip area columns is a vertical scribe area SLv, and an area between adjacent chip area rows is a horizontal scribe area SLh. In these lateral scribe areas SLh, horizontal alignment marks Am11 and Am12 for positioning the reticle in the horizontal direction with respect to the wafer are formed, and in these vertical scribe areas SLv, the vertical direction of the reticle with respect to the wafer is formed. Vertical alignment marks Am21 and Am22 for positioning are formed. Here, the alignment marks Am11 and Am21 are formed, for example, by patterning a polysilicon layer or the like in a process of forming a gate electrode constituting a circuit element or the like, and the alignment marks Am12 and Am22 are formed of a metal wiring. And formed by patterning a metal film.

  In the latter half of the process, for example, after the color filter forming process is performed, the microlens forming process is performed in two processes as described above.

  That is, after applying a photosensitive lens material on the wafer Wf, the lens material on the wafer Wf is exposed by the exposure apparatus 110 shown in FIG.

  Specifically, the exposure mask (first process reticle) used in the first microlens formation process is aligned with the wafer using the alignment marks Am12 and Am22 formed in the wiring process, and is then placed on the wafer. The applied lens material is exposed. Thereafter, the exposed lens material is developed, and the lens material is located at a predetermined pixel (a pixel located at the intersection of the odd-numbered pixel row and the odd-numbered pixel column, and a intersection of the even-numbered pixel row and the even-numbered pixel column). The developed lens material (lens member) is then melted and cured by heat treatment. Thus, the first microlens is placed on the pixel located at the intersection of the odd pixel row and the odd pixel column in the pixel array of each chip and the pixel located at the intersection of the even pixel row and the even pixel column. It is formed.

  Next, after a photosensitive lens material is applied on the wafer Wf on which the first microlenses are formed, the lens material on the wafer Wf is exposed by the exposure apparatus 110 shown in FIG. Specifically, the exposure mask (second process reticle) used in the second microlens formation process uses the alignment marks Am12 and Am22 formed in the wiring process as in the first microlens formation process. And aligning with the wafer, and exposing the lens material applied on the wafer. Thereafter, the exposed lens material is developed and patterned so that the lens material remains only on pixels other than the pixel on which the first microlens is formed, and then the developed lens material (for lens) The member is melted and cured by heat treatment. Thereby, in the pixel array of each chip, the pixels other than the pixel on which the first microlens is formed (the pixel at the intersection of the odd-numbered pixel row and the even-numbered pixel column, and the intersection of the even-numbered pixel row and the odd-numbered pixel column) The second microlens is formed on the pixel located at (1).

However, as described above, in the first microlens formation step and the second microlens formation step, when the alignment mark formed in the formation step such as a wiring layer which is a lower layer than the first microlens is used, Both the arrangement patterns of the first microlens and the second microlens are aligned with the pattern of the wiring layer, and the alignment accuracy of both the first microlens and the second microlens is the position of each. This includes variations in alignment.
JP 2000-22117 A JP 2000-260968 A JP 2000-269474 A JP 2000-332226 A JP 2003-332547 A JP 2006-66931 A JP 2003-229550 A JP 2007-47569 A

  As described above, in the conventional microlens formation method, when the microlens formation is performed in two steps, the alignment mark formed below the microlens formed in the first microlens formation step is used. In this case, the microlens formed in the second microlens formation step is aligned. In this case, the microlens formed in the first microlens formation step and the second microlens formation step is a mask twice. It will be aligned by the alignment.

  Thus, by dividing the microlens formation process into two steps, the lens non-formation region can be minimized and more light can be collected. However, since the microlens is formed twice, Deviations are likely to occur in the formation positions of the microlenses formed in one step and the microlenses formed in the second step. Since the misalignment between the microlenses leads to the occurrence of shading failure, the misalignment between the microlenses needs to be controlled to a minimum. However, at present, in the technique of forming the microlens in two parts, the controllability of the formation position between the microlenses (alignment deviation between the microlens formed in the first step and the microlens formed in the second step). There are no reported cases.

  The present invention has been made in order to solve the above-described conventional problems. When the microlens is formed in two steps, the microlens formed in the first step and the microlens formed in the second step are provided. The alignment accuracy with the lens can be increased, thereby making it possible to collect more light by minimizing the area where the lens is not formed, and also due to misalignment between the microlenses created in each process A method for forming a microlens capable of reducing shading defects, a method for manufacturing a solid-state imaging device using such a method for forming a microlens, and a solid-state imaging device obtained by the method for manufacturing the solid-state imaging device The purpose is to obtain electronic information equipment.

A method of forming a microlens according to the present invention is a method of forming a plurality of microlenses arranged in a matrix on a base layer, and the first is formed on a pixel array formed by arranging a plurality of pixels in a matrix. Are selected so that a plurality of first pixel regions in which the first microlenses are formed and a plurality of second pixel regions in which the first microlenses are not formed in a checkered pattern. A first lens step for forming the first microlens, and a second lens step for forming a second microlens in the second pixel region of the pixel array where the first microlens is not formed. The lens process includes a step of forming a first lens material layer by applying a thermosetting photosensitive lens material that is melt-cured by heat treatment on the underlayer, and the first lens material layer is formed as one exposure mask. Select using And exposing the exposed first lens material layer to form a first lens member on each of the plurality of first pixel regions, and on a predetermined region of the underlayer The step of forming the mark member, and the irradiation of the ultraviolet rays to the first lens member and the mark member, the melting of the mark member due to heat treatment is suppressed, and the first lens member is heated by dripping. Forming the first microlens by melt-curing the first lens member by simultaneously performing heat treatment on the first lens member and the mark member, and curing the mark member. and forming an alignment mark by, second lens step, Engineering for aligning the second microlens using the alignment mark formed by the first lens steps It is intended to include the above-described object can be achieved.

The present invention provides the method for forming a microlens, wherein the exposure mask used in the first lens step is formed so that a first circular lens-shaped member is formed by exposure and development of the first lens material layer. the aperture pattern of the portion corresponding to each of the first pixel region is circular shape, and, so that the mark member of planar rectangular shape is formed by exposure and development of said first lens material layer, the mark member is formed It is preferable that the opening pattern of the portion corresponding to the region to be formed has a rectangular shape.

According to the present invention, in the microlens formation method, the second lens step includes a step of applying a photosensitive lens material on the underlayer and the first microlens to form a second lens material layer. a step of selectively exposing using the second lens material layer an exposure mask, and developing the second lens material layer that is the exposed, first on each of the plurality of second pixel regions It is preferable to include a step of forming a two-lens member and a step of forming the second microlens by melting and curing the second lens member by heat treatment.

According to the present invention, in the microlens formation method, the exposure mask used in the second lens step is formed so that the second lens member having a planar circular shape is formed by exposure and development of the second lens material layer. It is preferable that an opening pattern of a portion corresponding to each of the second pixel regions is a circular shape.

According to the present invention, in the method for forming a microlens, the ultraviolet irradiation step of irradiating the first lens member and the mark member with ultraviolet rays includes: irradiating the mark member with ultraviolet rays; and the first lens member. It is preferable that it is the process of performing ultraviolet irradiation to under the conditions from which ultraviolet irradiation amount differs.

The present invention provides a method of forming the micro lenses, the UV irradiation step, the ultraviolet irradiation of the mark member and the lens member, the amount of UV irradiation to the mark member to said first lens member It is preferable that it is a process performed so that it may exceed the amount of ultraviolet irradiation of.

According to the present invention, in the microlens formation method, the ultraviolet irradiation step includes a first UV step of selectively irradiating only the mark member with ultraviolet rays, and both the mark member and the first lens member. And a second UV step of irradiating with ultraviolet rays.

  In the method for forming a microlens according to the present invention, it is preferable that the ultraviolet irradiation power in the first UV process is larger than the ultraviolet irradiation power in the second UV process.

The alignment mark optimizing method according to the present invention is formed simultaneously with the microlens in the first step when the plurality of microlenses are formed separately in the first and second steps, and is positioned in the second step. A method of optimizing the formation process of alignment marks used for alignment, the step of preparing a plurality of samples formed by forming microlenses on a substrate by changing parameters in the formation process of the alignment marks, and each sample A step of detecting a positional deviation amount between the first position confirmation mark formed simultaneously with the microlens in the first step and the second position confirmation mark formed simultaneously with the microlens in the second step; Based on the amount of displacement of the first and second position confirmation marks in each detected sample, the optimum alignment mark forming process is performed. And a step of determining parameters, said first step includes the steps of forming a lens material layer by applying a photosensitive lens material of the thermosetting type that melted and cured by heat treatment on the substrate, the lens material layer Selectively exposing using one exposure mask; developing the exposed lens material layer to form a lens member; and forming a mark member to be the alignment mark; When the first lens member and the mark member are irradiated with ultraviolet rays, melting of the mark member due to heat treatment is suppressed under a predetermined ultraviolet ray irradiation amount as the parameter, and the first lens member is heated. The first microlens is formed by subjecting the first lens member and the mark member to heat treatment at the same time by subjecting the lens shape to the lens shape, and by melting and hardening the first lens member. Forming a lens, and a step of forming an alignment mark by the curing of the mark member is Dressings containing the above objects can be achieved.

  In the alignment mark optimization method according to the present invention, in the first step, the first step is to place a first microlens on a lattice lens area formed by arranging a plurality of lens formation areas in a matrix. Forming a plurality of first lens forming regions formed with a plurality of second lens forming regions not formed with the first microlenses so as to form a checkered lattice pattern, The second step is preferably a step of forming a second microlens in a second lens formation region of the lattice lens region where the first microlens is not formed.

A method of manufacturing a solid-state imaging device according to the present invention includes: a pixel unit formed by arranging a plurality of pixels in a matrix; and a peripheral circuit unit that drives the pixel unit and processes a pixel signal from the pixel unit. A first half step of forming the pixel portion and the peripheral circuit portion in each chip region of the wafer, and a second half step of forming a plurality of microlenses in each chip region of the wafer; In the latter half step, the first microlens is formed on the pixel portion of each chip region, the plurality of first pixel regions in which the first microlens is formed, and the first microlens is formed. so that a plurality of second pixel regions which are not forms a checkerboard pattern, a first lens step of selectively forming, in the pixel portion, the second pixel region is not formed in the first microlens Second microphone And a second lens to form a lens, said first lens step, the step of forming the first lens material layer by applying a photosensitive lens material of the thermosetting type that melted and cured by heat treatment on the underlayer And selectively exposing the first lens material layer using one exposure mask, and developing the exposed first lens material layer on each of the plurality of first pixel regions. Forming a first lens member and forming a mark member on a predetermined region of the underlayer; and irradiating the first lens member and the mark member with ultraviolet rays by heat treatment. A step of suppressing melting of the member and causing the first lens member to have a lens shape by dripping; and heat-treating the first lens member and the mark member simultaneously to form the first lens member For melt hardening Ri the first microlens was formed, and forming an alignment mark by the curing of the mark member, the second lens step, said using an alignment mark formed by the first lens steps 2 includes the step of aligning the two microlenses, whereby the above object is achieved.

The present invention is the manufacturing method of the solid-state imaging device, in the first lens step, a predetermined area of the underlying layer, wherein the mark member is formed by development of the exposed lens material layer of the wafer it is preferably scribing unit.

In the method for manufacturing a solid-state imaging device according to the present invention, in the ultraviolet irradiation step of irradiating the first lens member and the mark member with ultraviolet rays , the mark member and the lens member are irradiated with ultraviolet rays. It is preferable that the step is performed so that the ultraviolet irradiation amount to the mark member is larger than the ultraviolet irradiation amount to the lens member.

In the method for manufacturing a solid-state imaging device according to the present invention, the ultraviolet irradiation step includes a first UV step of selectively irradiating only the mark member with ultraviolet rays, and both the mark member and the first lens member. It is preferable to include the 2nd UV process which irradiates ultraviolet rays.

In the method for manufacturing a solid-state imaging device according to the present invention, it is preferable that the ultraviolet irradiation power in the first UV process is larger than the ultraviolet irradiation power in the second UV process.

  The operation of the present invention will be described below.

  In the present invention, the first microlens is arranged on a pixel array formed by arranging a plurality of pixels in a matrix, the plurality of first pixel regions in which the first microlens is formed, and the first microlens. A first lens step of selectively forming a plurality of second pixel regions in which no lens is formed so as to form a checkered lattice pattern; and a second lens in which the first microlens of the pixel array is not formed. A second lens step of forming a second microlens in the pixel region, wherein the second lens step uses the alignment mark formed simultaneously with the first microlens in the first lens step. Therefore, the second microlens is directly aligned with the first microlens. For this reason, the microlens is divided in two steps. Click alignment becomes one, it is possible to reduce the deviation in the formation position of the microlens and the microlens to be formed at the second step of forming in the first step. As a result, it is possible to minimize the area where the lens is not formed, collect more light, and reduce shading failure due to misalignment between the microlenses created in each process.

According to the invention, in the first lens step, the lens member and the mark member are irradiated with ultraviolet rays after the development of the lens material layer and before the heat treatment, and the mark member and the lens Since the ultraviolet irradiation of the mark member is performed such that the ultraviolet irradiation amount of the mark member is larger than the ultraviolet irradiation amount of the lens member, the mark member is obtained from the mark material while suppressing the dripping of the mark member. The alignment accuracy by the alignment mark can be further improved.

  In other words, the microlens is formed in the first region constituting the checkered lattice pattern in the pixel array, and at the same time, the alignment mark is formed in the region other than the pixel array, and the alignment mark is irradiated with ultraviolet rays so as to suppress the dripping due to the heat treatment. Therefore, the shape of the alignment mark portion is prevented from being rounded, and a signal waveform with good contrast is obtained as an image signal of the alignment mark. As a result, when the microlens is formed in the second region constituting the lattice pattern of the pixel array, the alignment using the alignment mark can be performed with high accuracy.

  In the present invention, when the plurality of microlenses are formed in the first and second steps, the alignment marks are formed simultaneously with the microlenses in the first step and used for alignment in the second step. In the method for optimizing the forming process, in each sample, a first position confirmation mark formed simultaneously with the microlens in the first step and a second position confirmation mark formed simultaneously with the microlens in the second step A step of detecting a positional deviation amount from the mark, and a step of determining an optimum parameter in the alignment mark forming process based on the positional deviation amounts of the first and second position confirmation marks in the detected samples. Therefore, in the second step, an optimized alignment mark formed in the first step can be used. Efficiency can be increased while avoiding shading failure due to positional deviation between the adjacent microlenses.

  As described above, according to the present invention, the first microlens is arranged on the pixel array formed by arranging a plurality of pixels in a matrix, and the plurality of first pixel regions in which the first microlens is formed. A first lens step of selectively forming the plurality of second pixel regions in which the first microlenses are not formed so as to form a checkered lattice pattern, and the first microlens of the pixel array An alignment mark formed simultaneously with the first microlens in the first lens step. The second lens step forms a second microlens in a second pixel region that is not formed. Since the second microlens is aligned using the first microlens, the second microlens is directly aligned with the first microlens. Therefore, the microphone is divided into two steps. Lens mask alignment becomes one, it is possible to reduce the deviation in the formation position of the microlens and the microlens to be formed at the second step of forming in the first step. As a result, it is possible to minimize the area where the lens is not formed, collect more light, and reduce shading failure due to misalignment between the microlenses created in each process.

  According to the present invention, when a plurality of microlenses are formed in the first and second steps, the microlenses are formed at the same time as the microlenses in the first step, and are used for alignment in the second step. In the method for optimizing the alignment mark formation process, a step of preparing a plurality of samples formed by forming microlenses on a substrate by changing parameters in the alignment mark formation process; and Detecting a positional deviation amount between the first position confirmation mark formed simultaneously with the microlens in the step and the second position confirmation mark formed simultaneously with the microlens in the second step; A step of determining an optimum parameter in the alignment mark forming process based on the amount of displacement of the first and second position confirmation marks in the sample; Therefore, in the second step, the optimized alignment mark formed in the first step can be used, and the light collection efficiency by the microlens is reduced, and the shading failure due to the positional deviation between the adjacent microlenses is reduced. It can be increased while avoiding.

  According to the present invention, a solid-state imaging device having a pixel unit in which a plurality of pixels are arranged in a matrix and a peripheral circuit unit that drives the pixel unit and processes a pixel signal from the pixel unit is manufactured. A first half step of forming the pixel portion and the peripheral circuit portion in each chip region of the wafer, and a second half step of forming a plurality of microlenses in each chip region of the wafer, the second half step comprising: A first microlens is formed on a pixel array formed by arranging a plurality of pixels in a matrix, a plurality of first pixel regions in which the first microlens is formed, and the first microlens is formed. A first lens step that is selectively formed to form a checkered lattice pattern with a plurality of non-second pixel regions, and a second pixel region of the pixel array that is not formed with the first microlens. My A second lens step for forming a second lens, and in the second lens step, the alignment of the second microlens is performed using an alignment mark formed simultaneously with the first microlens in the first lens step. Since the second microlens is directly aligned with the first microlens, the microlens mask alignment performed in two steps is performed once and is formed in the first step. Deviation can be reduced in the formation position of the microlens and the microlens formed in the second step. As a result, it is possible to minimize the area where the lens is not formed, collect more light, and reduce shading failure due to misalignment between the microlenses created in each process.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
In the manufacturing method of the solid-state imaging device according to the first embodiment of the present invention, after forming the pixel portion and the peripheral circuit portion in each chip region of the wafer region in the first half step, the color filter is formed on the pixel portion in each chip region in the second half step. In the microlens forming method, the microlens is formed in two steps, and the second microlens to be formed in the second step is formed at the same time as the microlens in the first step. Positioning is performed using marks, and a method for forming such a microlens will be described below.

  1 to 4 are diagrams for explaining a method for forming the microlens, and FIG. 1 is a diagram for explaining an alignment mark formed in the first microlens formation step. FIG. 2 is a cross-sectional view for explaining the first microlens formation process, showing exposure (FIG. 2A), development (FIG. 2B), and bleaching (FIG. 2C). Yes. FIG. 3 is a cross-sectional view sequentially illustrating the heat treatment of the first microlens (FIG. 3A), the development of the second microlens (FIG. 3B), and the heat treatment step (FIG. 3C). . Further, FIG. 4 is a plan view showing a state after each processing in the first and second microlens forming steps, and after the development processing of the first microlens (FIG. 4A), The microlens and the alignment mark after heat treatment (FIG. 4B), after development processing of the second microlens (FIG. 4C), and after the heat treatment (FIG. 4D) are shown.

  First, on a surface region of a semiconductor substrate (wafer) 1, a pixel portion (not shown) formed by arranging a plurality of pixels and its peripheral circuit portion (not shown) are formed, and a planarizing film is formed on the entire surface. 2 is formed, a photosensitive thermoplastic resin is applied on the planarizing film 2 to form the lens material layer 10 of the first microlens. Subsequently, the lens material layer 10 is selectively exposed with the exposure light L using an exposure mask (reticle) 50 (FIG. 2A). At this time, the exposure mask 50 is aligned with the wafer Wf using the alignment marks Am12 and Am22 formed in the wiring layer forming step shown in FIG. The exposure mask 50 is formed by forming a light shielding film (chrome) 50b having a predetermined pattern on the surface of a transparent substrate 50a such as glass. The exposed portion (exposed portion) 10a of the lens material layer 10 is a portion that is soluble in the developer, and the unexposed portion (non-exposed portion) 10b of the lens material layer 10 is a portion that is not soluble in the developer. It is.

  Next, the lens material layer 10 is developed to selectively remove the exposed portion 10a of the lens material layer 10, and only the non-exposed portion 10b is placed on the planarizing film 2 with an alignment mark (mark member) 11h. And left as a lens member 11p (FIG. 2B). FIG. 4A shows an alignment mark 11h (see A part of FIG. 1) formed by the lens material layer 10 of the first microlens on the scribe part SLh of the wafer Wf and the chip area of the wafer Wf at this stage. The planar shape of the patterned lens formation part 11p (refer the B section of FIG. 1) formed in Rc is shown.

  Thereafter, the lens forming portion 11p and the alignment mark 11h are subjected to a bleaching process by ultraviolet (UV) irradiation (FIG. 2C). Subsequently, the lens forming portion 11p is melted and cured by heat treatment on the lens forming portion 11p and the alignment mark 11h to form the microlens 12p (FIG. 3A). At this time, the alignment mark 11h is also melted and cured to form a rounded mark 12h. FIG. 4B shows an alignment mark 12h formed by the lens material layer 10 of the first microlens on the scribe portion SLh of the wafer Wf and the first region formed on the chip region Rc of the wafer Wf at this stage. The planar shape of the microlens 12p is shown.

  Further, similar to the first microlens formation step, a photosensitive thermoplastic resin is applied to the entire surface to form a lens material layer of the second microlens, and then this lens material layer is exposed. A mask (reticle) is used to selectively expose with exposure light.

  At this time, the exposure mask is aligned with the wafer Wf using the alignment marks 11h and 11v formed in the first microlens forming step shown in FIG.

  Next, the lens material layer of the second microlens is developed to selectively remove the non-exposed portion of the lens material layer, and only the exposed portion is formed on the planarizing film 2 as the lens forming portion 21p. Leave (FIG. 3B). FIG. 4C shows that at this stage, the alignment mark 12h formed of the lens material layer 10 of the first microlens on the scribe portion SLh of the wafer Wf and the pattern formed on the chip region Rc of the wafer Wf are patterned. The planar shape of the lens forming portion 21p is shown together with the first microlens 12p.

  Subsequently, the lens forming portion 21p is melted and cured by heat treatment on the lens forming portion 21p to form the microlens 22p (FIG. 3C). FIG. 4D shows an alignment mark 12h formed by the lens material layer 10 of the first microlens on the scribe portion SLh of the wafer Wf and the first and second chips formed on the chip region Rc of the wafer Wf at this stage. The planar shape of the second microlenses 12p and 22p is shown.

  When alignment of the exposure mask is performed in the second microlens formation step using the alignment marks 11h and 11v formed in the first microlens formation step in this manner, the first microlens is aligned with the first microlens. Since the second microlens is formed by alignment, the mask alignment is performed once.

  As described above, in the first embodiment, the first microlens 12p is arranged on the pixel array formed by arranging a plurality of pixels in a matrix, and the plurality of first pixel regions in which the first microlens is formed; A first lens step of selectively forming a plurality of second pixel regions in which the first microlenses are not formed so as to form a checkered lattice pattern; and forming the first microlens of the pixel array An alignment mark formed simultaneously with the first microlens in the first lens step in the second lens step. Since the second microlens is aligned using 11v and 11h, the second microlens is directly aligned with the first microlens. , Mask alignment of microlenses are separately performed in two steps becomes one, it is possible to reduce the deviation in the formation position of the microlens and the microlens to be formed at the second step of forming in the first step. As a result, it is possible to minimize the area where the lens is not formed, collect more light, and reduce shading failure due to misalignment between the microlenses created in each process.

  In the first embodiment, the planar shape of the microlens formed in the second microlens process is circular, but it may be substantially rectangular.

(Embodiment 2)
The manufacturing method of the solid-state imaging device according to the second embodiment of the present invention is similar to the first embodiment. After the pixel portion and the peripheral circuit portion are formed in each chip region of the wafer region in the first half step, In the method for forming a color filter and a microlens on a pixel portion, the microlens is formed in two steps, and the second microlens to be formed in the second step is replaced with the microlens in the first step. In this embodiment, in the first lens process, the lens member and the mark are formed after the development of the lens material layer and before the heat treatment. irradiated with ultraviolet rays use member, the ultraviolet irradiation of the mark member and the lens member, the amount of ultraviolet irradiation is part for the lens to the mark member By performing to be more than the amount of ultraviolet irradiation to have so as to further improve the accuracy alignment by the alignment marks obtained from the mark material by suppressing the sagging of the mark member.

  Hereinafter, a method for forming the microlens according to the second embodiment will be described.

  FIG. 5 to FIG. 7 are views for explaining a method for forming this microlens, and FIG. 5 is a cross-sectional view for explaining a step of forming the first microlens, in which exposure (FIG. 5 (a)) and development are performed. (FIG. 5B) shows the first bleaching process (FIG. 5C). 6 shows a second bleaching process (FIG. 6A), a heat treatment of the first microlens (FIG. 6B), a development of the second microlens (FIG. 6C), and a heat treatment process (FIG. 6). 6 (d)) is a cross-sectional view sequentially showing. Further, FIG. 7 is a plan view showing a state after each processing in the first and second microlens forming steps, and after the development processing of the first microlens (FIG. 7A), The microlens and the alignment mark after heat treatment (FIG. 7B), after development processing of the second microlens (FIG. 7C), and after the heat treatment (FIG. 7D) are shown.

  First, on a surface region of the semiconductor substrate 1, a pixel portion (not shown) formed by arranging a plurality of pixels and its peripheral circuit (not shown) are formed, and further, a planarizing film 2 is formed on the entire surface. Thereafter, a photosensitive thermoplastic resin is applied onto the planarizing film 2 to form the lens material layer 10 of the first microlens. Subsequently, the lens material layer 10 is selectively exposed with the exposure light L using an exposure mask (reticle) 50 (FIG. 5A). At this time, the exposure mask 50 is aligned with the wafer Wf using the alignment marks Am12 and Am22 formed in the step of forming a light shielding film such as a wiring layer shown in FIG. The exposure mask 50 is the same as that in the first embodiment. The exposed portion (exposed portion) 10a of the lens material layer 10 is a portion that is soluble in the developer, and the unexposed portion (non-exposed portion) 10b of the lens material layer 10 is a portion that is not soluble in the developer. It is.

  Next, as in the first embodiment, the lens material layer 10 is developed to selectively remove the exposed portion 10a of the lens material layer 10, and only the non-exposed portion 10b is aligned on the planarizing film 2. 11h and the lens forming portion 11p are left (FIG. 5B). FIG. 7A shows that at this stage, the alignment mark 11h formed by the lens material layer 10 of the first microlens on the scribe portion SLh of the wafer Wf and the pattern formed on the chip region Rc of the wafer Wf are patterned. The planar shape of the lens formation part 11p is shown.

  Thereafter, using the light shielding mask 60 including the transparent glass substrate 60a and the light shielding portion 60b, only the alignment mark 11h of the lens forming portion (lens member) 11p and the alignment mark 11h is irradiated with ultraviolet (UV) Luv1. A first bleaching process is performed by irradiation (FIG. 5C). Subsequently, a second bleaching process is performed on the lens forming portion (lens member) 11p and the alignment mark 11h by irradiation with ultraviolet (UV) Luv2 (FIG. 6A). Here, the first bleaching process is performed with a higher ultraviolet irradiation power than the second bleaching process. Thereafter, the lens forming portion 11p is melted and cured by heat treatment on the lens forming portion 11p and the alignment mark 11h to form the microlens 12p (FIG. 6B). At this time, no alignment occurs in the alignment mark 11h because the above-mentioned two bleaching processes have been performed. FIG. 7B shows an alignment mark 111h formed by the lens material layer 10 of the first microlens on the scribe portion SLh of the wafer Wf and the first region formed on the chip region Rc of the wafer Wf at this stage. The planar shape of the microlens 12p is shown.

  Further, similar to the first microlens formation step, a photosensitive thermoplastic resin is applied to the entire surface to form a lens material layer of the second microlens, and then this lens material layer is exposed. Using a mask (reticle) (not shown), the exposure light L selectively exposes.

  At this time, the exposure mask is aligned with the wafer Wf using the alignment mark 111h formed in the first microlens formation step shown in FIG.

  Next, the lens material layer of the second microlens is developed to selectively remove the exposed portion of the lens material layer, and only the non-exposed portion is formed on the planarizing film 2 as the lens forming portion 21p. Leave (FIG. 6C). FIG. 7C shows that at this stage, the alignment mark 111h formed by the lens material layer 10 of the first microlens on the scribe portion SLh of the wafer Wf and the pattern formed on the chip region Rc of the wafer Wf are patterned. The planar shape of the lens forming portion 21p is shown together with the first microlens 12p.

  Subsequently, the lens forming portion 21p is melted and cured by heat treatment on the lens forming portion 21p to form the microlens 22p (FIG. 6D). FIG. 7D shows an alignment mark 111h formed by the lens material layer 10 of the first microlens on the scribe portion SLh of the wafer Wf and the first and second chips formed on the chip region Rc of the wafer Wf at this stage. The planar shape of the second microlenses 12p and 22p is shown.

As described above, in the second embodiment, in the first lens step, the lens member and the mark member are irradiated with ultraviolet rays after the development of the lens material layer and before the heat treatment. Since the ultraviolet irradiation to the lens member is performed such that the ultraviolet irradiation amount to the mark member is larger than the ultraviolet irradiation amount to the lens member, in addition to the effect of the first embodiment, the mark member It is possible to further improve the alignment accuracy by the alignment mark obtained from the mark material.

  In other words, only the alignment mark portion formed in the first microlens process is subjected to a UV irradiation process stronger than the microlens area in the bleaching process before the melt process. As a result, the amount of melt is reduced only in the alignment mark portion, and it becomes possible to prevent the shape from being rounded due to thermal sag of the alignment mark shape, thereby maintaining a rectangular shape. Therefore, it is possible to prevent the deterioration of the signal waveform used in the alignment process during the exposure process, the amount of misalignment between the microlens formed in the first process and the microlens formed in the second process can be reduced, and color shading failure Can be prevented.

  Since the melt amount and the amount of change in shape change depending on the UV irradiation power, the UV irradiation power only for the alignment mark portion is subjected to the UV irradiation power processing that provides the best alignment processing accuracy, and then the patterned lens material layer. It is possible to minimize the amount of misalignment of the microlenses formed in the first step and the second step.

Hereinafter, a method for optimizing such UV irradiation power will be described as a third embodiment.
(Embodiment 3)
FIG. 8 is a diagram for explaining an alignment mark optimization method according to Embodiment 3 of the present invention. In FIG. 8, the same reference numerals as those in FIG. 1 denote the same parts as those in the first embodiment.

  The alignment mark optimization method according to the third embodiment is formed simultaneously with the microlens in the first step when the plurality of microlenses are formed in the first and second steps, and in the second step. This is a method of optimizing the forming process of the alignment marks 111h and 111v used for alignment.

  That is, the alignment mark optimization method of the third embodiment prepares a plurality of samples (solid-state imaging device chips) formed by forming microlenses on the substrate by changing parameters in the formation process of the alignment marks 111h and 111v. A first position confirmation mark M2a formed simultaneously with the microlens in the first step and a second position confirmation mark M2b formed simultaneously with the microlens in the second step A step of detecting a positional deviation amount, and a step of determining an optimum parameter in the alignment mark forming process based on the positional deviation amounts of the first and second position confirmation marks in the detected samples. Yes.

  Here, in the first step, the first microlens is placed on a lattice lens area (pixel array) Ap formed by arranging a plurality of lens formation areas (pixel areas) in a matrix. The plurality of first lens formation regions (pixel regions) in which the first microlenses are formed and the plurality of second lens formation regions (pixel regions) in which the first microlenses are not formed have a checkered pattern. It is the process of forming. The second step is a step of forming a second microlens in a second lens formation region (pixel region) where the first microlens is not formed in the lattice lens region (pixel array) Ap. is there.

  Further, as described in the first and second embodiments, the first step includes a step of applying a photosensitive lens material on the substrate (wafer) Wf to form a lens material layer, and the lens material layer. Selectively exposing using an exposure mask; developing the exposed lens material layer to form a first lens member on each of the plurality of first lens forming regions; and Forming a mark member to be the alignment mark on the predetermined region, and melting and hardening the first lens member by heat treatment to form a first microlens.

  Further, the first step includes an ultraviolet irradiation step of irradiating the lens member and the mark member with ultraviolet rays after the development of the lens material layer and before the heat treatment. Further, the parameter in the alignment mark forming process is an ultraviolet ray irradiation amount in the ultraviolet ray irradiation step in the first step.

In the alignment mark optimizing method of the third embodiment, when the plurality of microlenses are formed in the first and second steps, the microlenses are formed simultaneously with the microlenses in the first step, and the second In a method for optimizing the formation process of alignment marks used for alignment in the process, a step of preparing a plurality of samples formed by forming microlenses on a substrate by changing parameters in the alignment mark formation process; In the sample, the amount of displacement between the first position confirmation mark M2a formed simultaneously with the microlens in the first step and the second position confirmation mark M2b formed simultaneously with the microlens in the second step is detected. And the alignment mark based on the detected positional deviation amount of the first and second position confirmation marks in each sample. And the step of determining the optimum parameter (UV irradiation amount) in the forming process. Therefore, in the second step, the optimized alignment mark formed in the first step can be used, and the light collection efficiency by the microlens can be increased. Further, it is possible to further improve the shading while avoiding the shading failure due to the positional deviation between the adjacent microlenses.
(Embodiment 4)
Although not specifically described in the first and second embodiments, for example, a digital video camera or a digital still camera using the solid-state imaging device created by the manufacturing method of the solid-state imaging device of the first or second embodiment as an imaging unit. An electronic information device having an image input device such as a digital camera such as the above, an image input camera, a scanner, a facsimile, and a camera-equipped mobile phone device will be described. The electronic information device of the present invention performs data recording after performing predetermined signal processing for recording high-quality image data obtained by using at least one of the solid-state imaging devices of Embodiments 1 and 2 of the present invention as an imaging unit. A memory unit such as a recording medium, a display unit such as a liquid crystal display device that displays the image data on a display screen such as a liquid crystal display screen after performing predetermined signal processing for display, and the image data for communication At least one of communication means such as a transmission / reception device that performs communication processing after the signal processing and image output means for printing (printing) and outputting (printing out) the image data.

  As mentioned above, although this invention has been illustrated using preferable embodiment of this invention, this invention should not be limited and limited to this embodiment. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range based on the description of the present invention and the common general technical knowledge from the description of specific preferred embodiments of the present invention. It is understood that the patent documents cited in the present specification should be incorporated by reference into the present specification in the same manner as the content itself is specifically described in the present specification.

  In the field of the microlens formation method, the solid-state imaging device manufacturing method, and the electronic information device, the present invention provides a microlens formed in the first step and the microlens formed in the first step when forming the microlens in two steps. The alignment accuracy with the microlens created in two steps can be improved, thereby making it possible to collect more light by minimizing the area where the lens is not formed, and the microlens created in each step. It is possible to reduce shading defects due to positional misalignment.

FIG. 1 is a diagram for explaining a method for manufacturing a solid-state imaging device according to Embodiment 1 of the present invention, and is a diagram for explaining alignment marks formed in a first microlens formation process. FIG. 2 is a diagram for explaining the manufacturing method of the solid-state imaging device according to the first embodiment, and is a cross-sectional view for explaining the first microlens formation process. Exposure (FIG. 2A), development (FIG. 2 (b)) and bleaching (FIG. 2 (c)). FIG. 3 is a diagram for explaining the method of manufacturing the solid-state imaging device according to the first embodiment, in which the heat treatment of the first microlens (FIG. 3A) and the development of the second microlens (FIG. 3B). ) And a heat treatment step (FIG. 3C) in order. FIG. 4 is a diagram for explaining the method of manufacturing the solid-state imaging device according to the first embodiment, and is a plan view illustrating a state after each process in the first and second microlens formation steps. After the microlens development process (FIG. 4A), the heat treatment (FIG. 4B), the second microlens development process (FIG. 4), and the heat treatment (FIG. 4). A lens and an alignment mark are shown. FIG. 5 is a diagram for explaining a method for manufacturing a solid-state imaging device according to Embodiment 2 of the present invention, which is a cross-sectional view for explaining a process for forming a first microlens, exposure (FIG. 5A), development (FIG. 5B) shows the first bleaching process (FIG. 5C). FIG. 6 is a diagram for explaining a method of manufacturing the solid-state imaging device according to the second embodiment. The second bleaching process (FIG. 6A), the heat treatment of the first microlens (FIG. 6B), the first FIG. 6 is a cross-sectional view sequentially showing development (FIG. 6C) and heat treatment step (FIG. 6D) of No. 2 microlens. FIG. 7 is a diagram for explaining the manufacturing method of the solid-state imaging device according to the second embodiment, and is a plan view showing a state after each processing in the first and second microlens forming steps. After the microlens development process (FIG. 7A), after the heat treatment (FIG. 7B), after the second microlens development process (FIG. 7C), and after the heat treatment (FIG. 7). The microlens and alignment mark of (d)) are shown. FIG. 8 is a diagram showing an alignment mark optimizing method according to Embodiment 3 of the present invention, and shows position confirmation marks formed in each film forming process. FIG. 9 is a diagram for explaining a conventional method for manufacturing a solid-state imaging device, and FIGS. 9A to 9C particularly show the steps of forming microlenses in the order of processing. FIG. 10 is a view for explaining an exposure apparatus used for forming the microlens and shows a schematic configuration thereof. FIG. 11 is a diagram for explaining a method of performing exposure processing on a wafer using the exposure apparatus 110 shown in FIG. FIG. 12 is an enlarged view of the surface area of the wafer Wf shown in FIG. 11. In the area (chip area) in which the solid-state imaging element chip (solid-state imaging device) is formed, and when each chip is cut out from the wafer The scribe areas SLv and SLh to be cut are enlarged.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Flattening film 10 Lens material layer 10a Exposed part 10b Non-exposed part 11h Alignment mark (marking member)
11p Lens member (lens forming part)
12p first microlens 22p second microlens 50 exposure mask (reticle)
50a Transparent substrate 50b Light-shielding film (chrome)
Wf wafer SLh, SLv scribe part

Claims (15)

A method of forming a plurality of microlenses arranged in a matrix on an underlayer,
A first microlens is formed on a pixel array formed by arranging a plurality of pixels in a matrix, a plurality of first pixel regions in which the first microlens is formed, and the first microlens is formed. A first lens step of selectively forming a plurality of second pixel regions not to form a checkered lattice pattern;
A second lens step of forming a second microlens in a second pixel region of the pixel array where the first microlens is not formed,
The first lens step includes
Applying a thermosetting photosensitive lens material that is melt-cured by heat treatment on the underlayer to form a first lens material layer;
Selectively exposing the first lens material layer using one exposure mask;
By developing the exposed first lens material layer, a first lens member is formed on each of the plurality of first pixel regions, and a mark member is formed on a predetermined region of the base layer. Process,
Irradiating the first lens member and the mark member with ultraviolet rays so that melting of the mark member due to heat treatment is suppressed and the first lens member has a lens shape due to thermal dripping; and
A step of simultaneously heat-treating the first lens member and the mark member to form a first microlens by melting and curing the first lens member, and forming an alignment mark by curing the mark member; Including
The method of forming a microlens, wherein the second lens step includes a step of aligning the second microlens using the alignment mark formed in the first lens step. The exposure mask used in the first lens step has an opening corresponding to each of the first pixel regions so that a first circular lens-shaped member is formed by exposure and development of the first lens material layer. the pattern was a circular shape, and so that the exposure and development of said first lens material layer mark member of planar rectangular shape is formed a rectangular opening pattern of the portion corresponding to the area where the mark member is formed The method for forming a microlens according to claim 1 , wherein the microlens is shaped. The second lens step includes
Applying a photosensitive lens material on the underlayer and the first microlens to form a second lens material layer;
Selectively exposing by using an exposure mask the second lens material layer,
Developing the exposed second lens material layer to form a second lens member on each of the plurality of second pixel regions;
The method for forming a microlens according to claim 1 , further comprising: melt-curing the second lens member by heat treatment to form a second microlens. The exposure mask used in the second lens process is a portion corresponding to each of the second pixel regions so that the second lens member having a planar circular shape is formed by exposure and development of the second lens material layer. The method for forming a microlens according to claim 3 , wherein the opening pattern has a circular shape. The ultraviolet irradiation step for irradiating the ultraviolet to the first lens member and the mark member, and the ultraviolet irradiation to the mark member, ultraviolet irradiation and the ultraviolet irradiation amount is different conditions for the first lens member The method for forming a microlens according to claim 1 , which is a step performed in step 1 . The ultraviolet irradiation step, the ultraviolet irradiation of the mark member and the lens member, the amount of UV irradiation to the mark member is a step of carrying out to be more than the amount of ultraviolet irradiation to said first lens member The method for forming a microlens according to claim 5 . The ultraviolet irradiation step includes
A first UV step of selectively irradiating ultraviolet rays only to the mark member;
The method for forming a microlens according to claim 6 , further comprising a second UV step of irradiating both the mark member and the first lens member with ultraviolet rays. The method for forming a microlens according to claim 7 , wherein an ultraviolet irradiation power in the first UV process is larger than an ultraviolet irradiation power in the second UV process. When forming a plurality of microlenses in two steps, the first and second steps are formed simultaneously with the microlens in the first step, and the alignment mark forming process used for alignment in the second step is optimized. A way to
Preparing a plurality of samples formed by changing the parameters in the alignment mark forming process and forming microlenses on the substrate;
In each sample, the amount of displacement between the first position confirmation mark formed simultaneously with the microlens in the first step and the second position confirmation mark formed simultaneously with the microlens in the second step is detected. And a process of
Determining an optimum parameter in the alignment mark formation process based on the amount of positional deviation of the first and second position confirmation marks in each detected sample,
The first step includes
Applying a thermosetting photosensitive lens material that is melt-cured by heat treatment on the substrate to form a lens material layer;
Selectively exposing the lens material layer using one exposure mask;
Developing the exposed lens material layer to form a lens member, and forming a mark member to be the alignment mark;
When the first lens member and the mark member are irradiated with ultraviolet rays, the mark member is prevented from being melted by heat treatment under a predetermined ultraviolet irradiation amount as the parameter, and the first lens member is A process of having a lens shape by heat dripping,
A step of simultaneously heat-treating the first lens member and the mark member to form a first microlens by melting and curing the first lens member, and forming an alignment mark by curing the mark member; including the alignment mark optimization methods. The first step includes
A first microlens is formed on a lattice lens region formed by arranging a plurality of lens formation regions in a matrix, the plurality of first lens formation regions in which the first microlens is formed, and the first microlens. A step of selectively forming a plurality of second lens formation regions in which lenses are not formed so as to form a checkered lattice pattern;
The second step includes
The alignment mark optimizing method according to claim 9 , which is a step of forming a second microlens in a second lens forming region in which the first microlens is not formed in the lattice lens region. A method of manufacturing a solid-state imaging device having a pixel unit formed by arranging a plurality of pixels in a matrix, and a peripheral circuit unit that drives the pixel unit and processes a pixel signal from the pixel unit,
A first half step of forming the pixel portion and the peripheral circuit portion in each chip region of the wafer;
A second half step of forming a plurality of microlenses in each chip region of the wafer,
The latter half of the process is
A first microlens is formed on a pixel portion of each chip region, a plurality of first pixel regions in which the first microlens is formed, and a plurality of second pixels in which the first microlens is not formed. A first lens step for selectively forming the region so as to form a checkered lattice pattern;
Wherein the pixel portion, and a second lens forming a second micro-lens in the second pixel region is not formed in the first microlens,
The first lens step includes
Forming a first lens material layer by applying a thermosetting photosensitive lens material that is melt-cured by heat treatment on the underlayer;
Selectively exposing the first lens material layer using one exposure mask;
By developing the exposed first lens material layer, a first lens member is formed on each of the plurality of first pixel regions, and a mark member is formed on a predetermined region of the base layer. Process,
Irradiating the first lens member and the mark member with ultraviolet rays so that melting of the mark member due to heat treatment is suppressed and the first lens member has a lens shape due to thermal dripping; and
A step of simultaneously heat-treating the first lens member and the mark member to form a first microlens by melting and curing the first lens member, and forming an alignment mark by curing the mark member; Including
The method of manufacturing a solid-state imaging device, wherein the second lens step includes a step of aligning the second microlens using the alignment mark formed in the first lens step. In the first lens step,
The predetermined region of the base layer, a method for manufacturing a solid-state imaging device according to 請 Motomeko 11 is a scribing portion of the wafer to the mark member is formed by development of the exposed lens material layer. In the ultraviolet irradiation process for irradiating the first lens member and the mark member with ultraviolet rays, the ultraviolet irradiation to the mark member and the lens member is performed , and the amount of ultraviolet irradiation to the mark member is used for the lens. The method for manufacturing a solid-state imaging device according to claim 12 , wherein the step is performed so as to increase the amount of ultraviolet irradiation to the member. The ultraviolet irradiation step includes
A first UV step of selectively irradiating ultraviolet rays only to the mark member;
The solid-state imaging device manufacturing method according to claim 13 , further comprising: a second UV step of irradiating both the mark member and the first lens member with ultraviolet rays. The method of manufacturing a solid-state imaging device according to claim 14 , wherein an ultraviolet irradiation power in the first UV process is larger than an ultraviolet irradiation power in the second UV process.

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