JP2013168468A - Solid-state imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-state imaging device provided with a light shielding part having good light shielding properties.SOLUTION: A light shielding part S provided in the solid-state imaging device has a laminated structure comprising: a lower light shielding material layer R1 which is a light shielding material layer containing a light shielding material; an intermediate high melting point material layer H2 which is a high melting point material layer containing a high melting point material and is formed on the upper surface of the lower light shielding material layer R1; and an upper light shielding material layer R2 which is a light shielding material layer and is formed on the upper surface of the intermediate high melting point material layer H2.

Description

  The present invention relates to a solid-state imaging device typified by a complementary metal oxide semiconductor (CMOS) image sensor and a charge coupled device (CCD) image sensor.

  In recent years, solid-state imaging devices such as a CCD image sensor and a CMOS image sensor are mounted on various electronic devices having an imaging function such as an imaging device such as a digital video camera and a digital still camera, and a mobile phone with a camera. In the solid-state imaging device, for example, a photoelectric conversion unit including a photodiode generates a charge by photoelectric conversion, and a potential of the charge is amplified to generate a signal constituting an image.

  In such a solid-state imaging device, a light-shielded pixel that detects dark current with a purpose of preventing light that has entered a pixel from entering adjacent pixels (color mixing) and a structure in which light does not enter a photoelectric conversion unit. For the purpose of providing, a light shielding portion for shielding light is formed. Note that, for example, a wiring made of metal also has a light shielding property, so that the wiring may function as a light shielding portion.

  Since such a light shielding portion is formed so as to be embedded in an interlayer insulating film, a passivation film, or the like, it is easily subjected to stress from the outside. Then, due to the stress received from the outside, a void due to stress migration occurs in the light shielding portion, which causes a problem because the light shielding performance deteriorates.

  Therefore, in Patent Document 1, for example, a silicon oxide film having a mechanical crack inferior to that of the wiring film and having microcracks is provided on the surface of the wiring film made of metal, and externally applied stress is absorbed or alleviated by the silicon oxide film. Thus, there has been proposed a semiconductor device in which the stress applied to the wiring film is reduced and the generation of voids is suppressed.

JP 2008-294327 A

  From the viewpoint of improving the sensitivity of the solid-state imaging device and preventing color mixing, it is preferable to reduce the film thickness of the light-shielding portion and shorten the distance from when light enters to the light-receiving portion. However, as the film thickness of the light shielding portion is reduced, voids penetrating in the film thickness direction are more likely to occur due to various heat treatment processes performed after the light shielding portion is formed, for example. Such a void penetrating the light shielding portion causes a problem because the light shielding performance of the light shielding portion is significantly reduced. Note that even if a silicon oxide film is formed on the surface of the light shielding portion as in the wiring film proposed in Patent Document 1, it is difficult to prevent voids penetrating in the film thickness direction as will be described later.

  Accordingly, an object of the present invention is to provide a solid-state imaging device including a light shielding portion having a good light shielding property.

  In order to achieve the above object, the present invention includes a substrate in which a photoelectric conversion unit that photoelectrically converts light incident from the upper surface is provided, and a light shielding unit provided above the upper surface of the substrate, The light-shielding portion is a light-shielding material layer having a light-shielding material, which is a lower light-shielding material layer and a refractory material layer having a refractory material, and is formed on the upper surface of the lower light-shielding material layer. Provided is a solid-state imaging device having a laminated structure including an intermediate refractory material layer and the light shielding material layer, and an upper light shielding material layer formed on an upper surface of the intermediate refractory material layer To do.

  According to this solid-state imaging device, even if a void occurs in the light shielding portion, the intermediate refractory material layer formed between the lower light shielding material layer and the upper light shielding material layer causes the upward and downward directions thereof. Propagation is prevented. Therefore, the void generated in the lower light-shielding material layer does not propagate to the upper light-shielding material layer, and the void generated in the upper light-shielding material layer does not propagate to the lower light-shielding material layer. Therefore, it is possible to prevent the formation of a void penetrating the light shielding material layer.

  Furthermore, in the solid-state imaging device having the above characteristics, it is preferable that the refractory material layer includes the refractory material having a melting point of 1000 ° C. or higher. Specifically, for example, in the solid-state imaging device having the above characteristics, it is preferable that the high melting point material layer includes at least one of titanium nitride, titanium, titanium tungsten, tungsten nitride, and tungsten.

  According to this solid-state imaging device, even if a heat treatment (at most 500 ° C.) is performed on the solid-state imaging device after the light-shielding portion is formed, it is possible to reduce the change in physical properties due to the heat treatment to be negligible.

  Furthermore, in the solid-state imaging device having the above characteristics, it is preferable that the thickness of the refractory material layer is 5 nm or more and 100 nm or less.

  According to this solid-state imaging device, it is possible to easily control the film thickness by setting the film thickness of the high melting point material layer to 5 nm or more, and to reduce the film forming speed for film thickness control. It is possible to prevent a decrease in mass production efficiency due to the above. In addition, by making the film thickness of the refractory material layer 100 nm or less, it is possible to reduce the stress generated in the refractory material layer, and the warpage of the substrate is increased by the stress, so that there is a defect in the substrate. It is possible to prevent the dark current from increasing.

  Furthermore, in the solid-state imaging device having the above characteristics, it is preferable that the light-shielding material layer includes aluminum. Furthermore, in the solid-state imaging device having the above characteristics, it is preferable that the thickness of the light-shielding material layer is 50 nm or more.

  According to this solid-state imaging device, it is possible to obtain good light shielding properties even if the light shielding material layer is thin. Specifically, from the viewpoint of improving the sensitivity of the solid-state imaging device and preventing color mixing, it is preferable to shorten the distance from the incidence of light until it reaches the light receiving unit, but if it is a light shielding material layer having aluminum, By setting the film thickness to 50 nm or more, it is possible to obtain good light shielding properties.

  Furthermore, in the solid-state imaging device having the above characteristics, the light shielding portion is one of the high melting point material layers, and the lower high melting point material layer formed on the lower surface of the lower light shielding material layer, and the high melting point It is preferable to further include an upper refractory material layer that is one of the material layers and is formed on the upper surface of the upper light-shielding material layer.

  According to this solid-state imaging device, it is possible to suppress the generation of voids in the lower light-shielding material layer and the upper light-shielding material layer by suppressing the stress received by the lower light-shielding material layer and the upper light-shielding material layer. It becomes possible.

  According to the solid-state imaging device having the above characteristics, by forming an intermediate high melting point material layer that prevents the propagation of voids inside the light shielding material layer, even if a void occurs, the light shielding material layer penetrates. It becomes possible to prevent development into a void. Therefore, it is possible to improve the light shielding property of the light shielding portion provided in the solid-state imaging device.

FIG. 2 is a schematic cross-sectional view showing a structural example of a solid-state imaging device according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing an example of the structure of a light shielding portion provided in the solid-state imaging device of FIG. 1. The typical sectional view showing a comparative light-shielding part. FIG. 5 is a schematic cross-sectional view showing a light shielding portion where a void has occurred and a comparative light shielding portion where a void has occurred. The typical top view which shows the chip | tip with which the void generate | occur | produced in each of the wafer which actually formed the light-shielding part, and the wafer which actually formed the comparison light-shielding part. The figure which shows the optical microscope image of a light-shielding part and a comparison light-shielding part.

<Overall structure>
First, a structural example of a solid-state imaging device according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view showing a structural example of a solid-state imaging device according to an embodiment of the present invention. In FIG. 1, a so-called surface irradiation type CMOS image sensor is illustrated as the solid-state imaging device 1 according to the embodiment of the present invention.

  As shown in FIG. 1, the solid-state imaging device 1 includes a substrate 10, a photoelectric conversion unit 11 that is formed in the substrate 10 and photoelectrically converts light incident from the upper surface 101 of the substrate 10, and generates photoelectric charges. A charge storage unit 111 that is a part of the conversion unit 11 and stores charges generated by photoelectric conversion; a floating diffusion unit 12 that is formed in the substrate 10 and to which charges stored in the charge storage unit 111 are transferred; An element isolation portion 13 formed between adjacent pixels in the substrate 10, a gate insulating film 14 formed on the upper surface 101 of the substrate 10 and between the charge storage portion 111 and the free diffusion portion 12, and a gate A transfer gate electrode 15 formed on the upper surface of the insulating film 14, a first interlayer insulating film 16 formed on the upper surface 101 of the substrate 10 to embed the transfer gate electrode 15, and a transfer gate penetrating the first interlayer insulating film 16. A gate contact 17 formed so as to be electrically connected to the electrode 15, an FD contact 18 formed so as to be electrically connected to the floating diffusion portion 12 through the first interlayer insulating film 16, and a gate contact 17, a gate wiring 19 electrically connected to 17, an FD wiring 20 electrically connected to the FD contact 18, and a second interlayer insulation formed on the first interlayer insulating film 16 to embed the gate wiring 19 and the FD wiring 20. A film 21, an inter-pixel light shielding portion 22 formed on the upper surface of the second interlayer insulating film 21, a third interlayer insulating film 23 formed on the upper surface of the second interlayer insulating film 21 and embedding the inter-pixel light shielding portion 22, A passivation film 24 formed on the upper surface of the third interlayer insulating film 23, and a color filter 2 formed on the upper surface of the passivation film 24 to selectively transmit light of a predetermined color (wavelength). When provided with a coating film 26 formed so as to fill the color filter 25, a microlens 27 for transmitting color filter 25 a light condensing incident is formed on the upper surface of the coating film 26, the.

  The photoelectric conversion unit 11 includes a charge storage unit 111 and a partial region of the substrate 10 around it. The substrate 10 is made of, for example, p-type or n-type silicon, and the charge storage unit 111 is made of, for example, silicon having a conductivity type opposite to that of the substrate 10 by ion implantation. That is, the photoelectric conversion unit 11 including the partial region of the substrate 10 and the charge storage unit 111 is a photodiode. Similarly to the charge storage unit 111, the floating diffusion unit 12 is also made of silicon having a conductivity type opposite to that of the substrate 10 by ion implantation, for example.

  The element isolation part 13 is an STI (Shallow Trench Isolation) formed by filling a trench (trench) formed in the substrate 10 with silicon oxide, for example, and the floating diffusion part 12 in one of two adjacent pixels and the charge in the other. Between the storage unit 111 and the storage unit 111. The gate insulating film 14 is made of, for example, silicon oxide, and the transfer gate electrode 15 is made of, for example, polysilicon.

  Each of the first interlayer insulating film 16, the second interlayer insulating film 21, and the third interlayer insulating film 23 is made of, for example, silicon oxide. Further, the passivation film 24 is made of, for example, silicon nitride.

  The gate contact 17 is formed by filling a hole (contact hole) formed at a position immediately above the transfer gate electrode 15 of the first interlayer insulating film 16 with a conductive material such as copper or aluminum. The same applies to the FD contact 18, and a hole (contact hole) formed at a position immediately above the floating diffusion portion 12 of the first interlayer insulating film 16 is filled with a conductive material such as copper or aluminum.

  The gate wiring 19 and the FD wiring 20 are formed by, for example, forming a predetermined film on the upper surface of the first interlayer insulating film 16 and then selectively removing unnecessary portions by etching. The same applies to the inter-pixel light shielding portion 22, for example, by forming a predetermined film on the upper surface of the second interlayer insulating film 21 and then selectively removing unnecessary portions by etching.

  The inter-pixel light-shielding unit 22 functions as a light-shielding unit for preventing light once incident on a pixel from entering an adjacent pixel (color mixing). Note that the gate wiring 19 and the FD wiring 20 may function not only as a wiring electrically connected to the gate contact 17 and the FD contact 18 but also as a light shielding portion similar to the inter-pixel light shielding portion 22. Details of the light shielding portion will be described later.

  The color filter 25 is made of, for example, a resin containing a pigment, and the pigment has a property of selectively transmitting light of a predetermined color (wavelength). The microlens 27 is made of, for example, resin, and has a convex shape to collect incident light on the color filter 25 and the lower side thereof. The coating film 26 is made of, for example, a resin, and is provided to improve surface flatness and adhesion between the third interlayer insulating film 23, the color filter 25, and the microlens 27.

  In the solid-state imaging device 1 illustrated in FIG. 1, the microlens 27, the color filter 25, and the charge storage unit 111 are aligned in a direction perpendicular to the upper surface 101 of the substrate 10 (up and down direction in the drawing). Each column constitutes each pixel. For example, these pixels are arranged in a matrix in a plane parallel to the upper surface 101 of the substrate 10. Specifically, for example, these pixels are arranged in a Bayer array when focusing on the color transmitted by the color filter 25.

  Light incident on the solid-state imaging device 1 is collected by the microlens 27, passes through the coat film 26, and passes through the color filter 25. At this time, the color filter 25 selectively transmits light of a predetermined color (wavelength). The light transmitted through the color filter 25 passes through the third interlayer insulating film 23, the second interlayer insulating film 21, and the first interlayer insulating film 16, and enters the substrate 10 from the upper surface 101. Electrons and holes are generated by photoelectric conversion by light incident on the substrate 10, and one of them is stored in the charge storage unit 111. For example, if the substrate 10 is p-type and the charge storage unit 111 is n-type, electrons generated by photoelectric conversion are stored in the charge storage unit 111. Conversely, if the substrate 10 is n-type and the charge storage unit 111 is p-type, holes generated by photoelectric conversion are stored in the charge storage unit 111.

  Next, when a predetermined potential is applied to the gate electrode 15 via the gate wiring 19 and the gate contact 17, the potential under the gate electrode 15 in the substrate 10 changes, and the charge accumulated in the charge accumulation unit 111. Moves to the floating diffusion part 12 and accumulates. Then, the electric potential due to the charges accumulated in the floating diffusion portion 12 is read through the FD contact 18 and the FD wiring 20.

<Light shielding part>
Next, the above-described light shielding portion will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view showing an example of the structure of the light shielding portion provided in the solid-state imaging device of FIG. As described above, the light shielding portion S shown in FIG. 2 corresponds to the inter-pixel light shielding portion 22 shown in FIG.

  As shown in FIG. 2, the light-shielding portion S includes a lower refractory material layer H1 formed on the substrate 10 side (lower side in FIG. 1) and a lower side formed on the upper surface of the lower refractory material layer H1. The light shielding material layer R1, the intermediate high melting point material layer H2 formed on the upper surface of the lower light shielding material layer R1, the upper light shielding material layer R2 formed on the upper surface of the intermediate high melting point material layer H2, and the upper light shielding material And an upper refractory material layer H3 formed on the upper surface of the conductive material layer R2.

  Each of the lower refractory material layer H1, the intermediate refractory material layer H2, and the upper refractory material layer H3 includes a refractory material layer having a refractory material. Considering that the heat treatment temperature performed on the solid-state imaging device 1 after the formation of the light-shielding portion S is at most 500 ° C., the refractory material layer has a refractory material having a melting point of 1000 ° C. or higher. If it exists, since the change of the physical property by heat processing can be made small so that it can be disregarded, it is preferable. Specifically, for example, it is preferable that the high melting point material layer has at least one of titanium nitride, titanium, titanium tungsten, tungsten nitride, and tungsten.

  The film thickness of the high melting point material layer constituting each of the lower high melting point material layer H1, the intermediate high melting point material layer H2, and the upper high melting point material layer H3 is preferably 5 nm or more and 100 nm or less. By making the film thickness of the refractory material layer 5 nm or more, it becomes possible to easily control the film thickness, and to prevent the mass production efficiency from being lowered by slowing the film forming speed to control the film thickness. It becomes possible to do. In addition, by setting the film thickness of the refractory material layer to 100 nm or less, it is possible to reduce the stress generated in the refractory material layer, and the warpage of the substrate 10 due to the stress increases, so that It is possible to prevent a defect from occurring and an increase in dark current.

  Each of the lower light-shielding material layer R1 and the upper light-shielding material layer R2 includes a light-shielding material layer having a light-shielding material. For example, it is preferable that the light-shielding material layer has aluminum because good light-shielding properties can be obtained even with a thin film thickness. Specifically, for example, it is preferable that the light-shielding material layer is made of aluminum and copper (composition ratio is less than 1%).

  The film thickness of the light-shielding material layer that constitutes each of the lower light-shielding material layer R1 and the upper light-shielding material layer R2 is preferably 50 nm or more. From the viewpoint of improving the sensitivity of the solid-state imaging device 1 and preventing color mixing, it is preferable to shorten the distance between the microlens 27 and the substrate 10, but if the light-shielding material layer has aluminum, the film thickness is 50 nm or more. By doing so, it is possible to obtain a good light shielding property.

  It should be noted that the elements and composition ratios of the materials constituting the lower refractory material layer H1, the intermediate refractory material layer H2, and the upper refractory material layer H3 may be different. Similarly, elements and composition ratios may be different for materials forming the lower light-shielding material layer R1 and the upper light-shielding material layer R2.

<Comparison result>
Next, the light shielding part S (hereinafter referred to as a comparative light shielding part compared to the light shielding part S) of the solid-state imaging device according to the embodiment of the present invention shown in FIG. The features will be explained. First, a light shielding part (hereinafter referred to as a comparative light shielding part) serving as a comparative example will be described with reference to FIG. FIG. 3 is a schematic cross-sectional view showing the comparative light-shielding portion, and corresponds to FIG.

  As shown in FIG. 3, the comparative light-shielding portion 100 is formed on the lower refractory material layer 101 that is the above-described refractory material layer, and on the upper surface of the lower refractory material layer 101 that is the above-described light-shielding material layer. Intermediate light-shielding material layer 102, upper refractory material layer 103 formed on the upper surface of intermediate light-shielding material layer 102, and made of silicon oxide and upper refractory material layer 103. And a silicon oxide layer 104 formed on the upper surface of the substrate.

  That is, the comparative light shielding part 100 shown in FIG. 3 is not provided with the intermediate high melting point material layer H2 as compared with the light shielding part S shown in FIG. The difference is that the layer 104 is provided.

  Next, the features of the light shielding portion S will be described in comparison with the comparative light shielding portion 100 while referring to FIGS. FIG. 4 is a schematic cross-sectional view showing a light shielding part where a void is generated and a comparative light shielding part where a void is generated. FIG. 5 is a schematic plan view showing a chip in which a void has occurred in each of a wafer in which a light shielding part is actually formed and a wafer in which a comparative light shielding part is actually formed. FIG. 6 is a diagram showing optical microscope images of the light shielding part and the comparative light shielding part. In each of FIGS. 4 to 6, (a) shows the light shielding part S, and (b) shows the comparative light shielding part 100. Further, the planes of the light shielding portion S and the comparative light shielding portion 100 shown in FIG. 6 are surfaces perpendicular to the cross sections shown in FIGS.

  As shown in FIG. 4A, in the light shielding portion S, even if a void V is generated, an intermediate high melting point material layer formed between the lower light shielding material layer R1 and the upper light shielding material layer R2. The vertical propagation is prevented by H2. Therefore, the void generated in the lower light-shielding material layer R1 does not propagate to the upper light-shielding material layer R2, and the void generated in the upper light-shielding material layer R2 does not propagate to the lower light-shielding material layer R1. It will be. Therefore, in the light shielding portion S, it is possible to prevent the formation of voids penetrating the light shielding material layers (the lower light shielding material layer R1 and the upper light shielding material layer R2).

  On the other hand, as shown in FIG. 4B, in the comparative light shielding unit 100, once the void V is generated, it propagates in the vertical direction. Therefore, in the comparative light shielding part 100, a void penetrating the light shielding material layer (intermediate light shielding material layer 102) is formed.

  As described above, in the solid-state imaging device 1 according to the embodiment of the present invention, even if the void V is generated by forming the intermediate high melting point material layer H2 that prevents the propagation of the void V in the light shielding portion S, It is possible to prevent the formation of a void penetrating the light shielding material layer (the lower light shielding material layer R1 and the upper light shielding material layer R2). Therefore, the light shielding property of the light shielding part S provided in the solid-state imaging device 1 according to the embodiment of the present invention can be improved.

  Further, as shown in FIG. 5 (a), the chip C in which the light-shielding portion S is formed has a probability that a void (having a major axis of 1 μm or more discovered by observation with an optical microscope, the same applies in the description of FIG. 5 below) is included. Can be made very low. In the example shown in FIG. 5A, all the chips C in the wafer W do not include voids, and the probability that the chip C in which the light shielding portion S is formed includes voids is 1%. Less than. Further, as shown in FIG. 6A, in the light shielding portion S, no conspicuous large void is observed.

  On the other hand, as shown in FIG. 5B, in the chip 201 in which the comparative light-shielding portion 100 is formed, the probability that a void is included increases. In the example shown in FIG. 5B, dozens of chips 201 having voids are confirmed near the outer edge of the wafer 200, and the probability that the chips 201 forming the comparative light shielding unit 100 include voids is about 11%. It becomes. In addition, as shown in FIG. 6B, a noticeably large void V is observed in the comparative light shielding unit 100.

  As described above, the light-shielding portion S employs a structure that prevents the formation of voids penetrating the light-shielding material layers (the lower light-shielding material layer R1 and the upper light-shielding material layer R2) as described above. It is possible to effectively reduce the probability that a conspicuously large void (that is, a void that causes a reduction in light shielding property) is formed in C. Therefore, the light shielding property of the light shielding part S provided in the solid-state imaging device 1 according to the embodiment of the present invention can be improved.

<Deformation, etc.>
[1] In order to prevent the generation of voids penetrating the light-shielding material layer, the lower light-shielding material layer R1 and the upper light-shielding material are used as in the light-shielding portion S shown in FIGS. 2 and 4A. A laminated structure in which the intermediate high-melting-point material layer H2 is formed between the layer R2 and the lower-melting-point material layer H1 and the upper-side high-melting-point material layer H3 is not necessarily required. However, not only the generation of voids penetrating the light-shielding material layer but also the lower light-shielding material layer R1 and the upper light-shielding material layer R1 and the upper light-shielding material layer R2 are suppressed by suppressing the stress received by the lower light-shielding material layer R1 and the upper light-shielding material layer R2. In order to suppress the generation of voids in the light shielding material layer R2, the lower refractory material layer H1 and the upper refractory material layer H3 are provided as in the light shielding portion S shown in FIGS. Is preferred.

  [2] Although the light shielding portion S shown in FIG. 2 is specifically described as corresponding to the inter-pixel light shielding portion 22 shown in FIG. 1, the gate wiring 19 and the FD wiring 20 of FIG. . In this case, all of the gate wiring 19, the FD wiring 20, and the inter-pixel light shielding portion 22 may have the same structure as the light shielding portion S shown in FIG. 2, but the materials and film thicknesses of the respective layers are not necessarily the same. There is no need. Further, for example, when the inter-pixel light shielding portion 22 is not provided, it is possible to configure only the gate wiring 19 and the FD wiring 20 in FIG. Further, only one of the gate wiring 19 and the FD wiring 20 shown in FIG.

  [3] The case where the light-shielding part S shown in FIG. 2 is applied to the inter-pixel light-shielding part 22 for preventing light once incident on the pixel from entering adjacent pixels (color mixing) has been illustrated. It is also possible to apply the part S to a light-shielded pixel that detects dark current. In this case, the light shielding part S is provided in the light shielding pixel, directly above the photoelectric conversion unit 111 (for example, in the same layer as the inter-pixel light shielding part 22 or in the same layer as the gate wiring 19 and the FD wiring).

  [4] As shown in FIG. 1, a so-called front-illuminated CMOS image sensor is exemplified as the solid-state imaging device 1 according to the embodiment of the present invention, but the present invention is a back-illuminated CMOS image sensor. However, the present invention can be applied to both front-illuminated and back-illuminated CCD image sensors and solid-state imaging devices other than CMOS image sensors and CCD image sensors.

  The solid-state imaging device according to the present invention can be suitably used for, for example, a CMOS image sensor or a CCD image sensor mounted on various electronic devices having an imaging function.

DESCRIPTION OF SYMBOLS 1: Solid-state image sensor 10: Board | substrate 101: Upper surface 11: Photoelectric conversion part 111: Charge storage part 12: Floating diffusion part 13: Element separation part 14: Gate insulating film 15: Transfer gate electrode 16: 1st interlayer insulation film 17: Gate contact 18: FD contact 19: Gate wiring 20: FD wiring 21: Second interlayer insulating film 22: Inter-pixel light shielding part 23: Third interlayer insulating film 24: Passivation film 25: Color filter 26: Coat film 27: Micro lens S: Light shielding part H1: Lower high melting point material layer H2: Middle high melting point material layer H3: Upper high melting point material layer R1: Lower light shielding material layer R2: Upper light shielding material layer V: Void W: Wafer C: Chip

Claims (7)

A substrate in which a photoelectric conversion unit for photoelectrically converting light incident from the upper surface is formed;
A light shielding portion provided above the upper surface of the substrate,
The shading part is
A lower light-shielding material layer that is a light-shielding material layer having a light-shielding material;
A high melting point material layer having a high melting point material, an intermediate high melting point material layer formed on the upper surface of the lower light-shielding material layer;
The light-shielding material layer, and an upper light-shielding material layer formed on an upper surface of the intermediate high-melting-point material layer;
A solid-state imaging device having a laminated structure made of   The solid-state imaging device according to claim 1, wherein the refractory material layer has the refractory material having a melting point of 1000 ° C. or higher.   The solid-state imaging device according to claim 2, wherein the refractory material layer includes at least one of titanium nitride, titanium, titanium tungsten, tungsten nitride, and tungsten.   4. The solid-state imaging device according to claim 1, wherein a film thickness of the refractory material layer is 5 nm or more and 100 nm or less.   The solid-state imaging device according to claim 1, wherein the light-shielding material layer includes aluminum.   The solid-state imaging device according to claim 5, wherein a thickness of the light-shielding material layer is 50 nm or more. The shading part is
One of the refractory material layers, a lower refractory material layer formed on the lower surface of the lower light-shielding material layer;
One of the refractory material layers, an upper refractory material layer formed on the upper surface of the upper light-shielding material layer;
The solid-state imaging device according to claim 1, further comprising: