JP2007150266A - Solid state imaging device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a parasitic capacitance of a floating diffusion part while adopting direct sticking structure. <P>SOLUTION: A light receiving part 21 and the floating diffusion part 22 are separately formed on a semiconductor substrate 20 (S11), and a light-transmitting adhesive agent 31 is applied to a region corresponding to the light receiving part 21 on the semiconductor substrate 20 (S22), and a light-transmitting plate material 30 is stuck on the semiconductor substrate 20 to which the light-transmitting adhesive agent 31 is applied (S23). Here, before applying the light-transmitting adhesive agent 31, a weir portion 24 on the semiconductor substrate 20 is so formed that the light-transmitting adhesive agent 31 applied to the region corresponding to the light receiving part 21 is prevented from flowing into the region corresponding to the floating diffusion part 22 on the semiconductor substrate 20 (S18). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a solid-state imaging device used for a digital camera or the like and a solid-state imaging device.

  In the field of solid-state imaging devices, extensive research and development has been conducted on technologies for achieving high sensitivity. Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique for increasing the sensitivity by reducing the parasitic capacitance of the floating diffusion portion (floating diffusion portion). In a general solid-state imaging device, a light receiving portion and a floating diffusion portion are formed on a semiconductor substrate so as to be separated from each other. The semiconductor substrate is covered with an organic film for surface protection. In Patent Document 1, a portion of the organic film that covers the floating diffusion portion is removed. In this way, since the parasitic capacitance of the floating diffusion portion is reduced, the voltage conversion efficiency of the floating diffusion portion is improved, and as a result, the solid-state imaging device can be highly sensitive.

On the other hand, as for the package structure of the solid-state imaging device, a direct tension structure has been proposed in place of the conventionally used hollow package structure (for example, Patent Document 2). The direct stretch structure refers to a structure in which a translucent plate material is attached to a semiconductor substrate having a light receiving portion and a floating diffusion portion with a translucent adhesive. The advantage of the direct pasting structure is that the difference in refractive index among the translucent plate material, translucent adhesive, and semiconductor substrate can be reduced by appropriately selecting the translucent adhesive. By reducing the difference in refractive index, the light reflection component at each boundary can be reduced, and as a result, the sensitivity of the solid-state imaging device can be increased.
JP-A-2-2675 JP 2000-323692 A

In recent years, the solid-state imaging device has a tendency that the signal charge is further reduced as the light receiving area per pixel is reduced. Therefore, it is conceivable to further increase the sensitivity of the solid-state imaging device by combining the structures described in Patent Document 1 and Patent Document 2 described above.
However, when the structures described in Patent Document 1 and Patent Document 2 are simply combined, a light-transmitting adhesive (an organic material such as an epoxy resin) flows out when the light-transmitting plate is attached to a semiconductor substrate. The problem of covering the floating diffusion occurs. In other words, even if the portion of the organic film on the semiconductor substrate that covers the floating diffusion portion is removed before the translucent plate is attached, the organic material (the translucent adhesive) is applied after the translucent plate is attached. Will cover the floating diffusion. Therefore, the parasitic capacitance of the floating diffusion portion cannot be reduced, and the high sensitivity of the solid-state imaging device cannot be achieved.

  In general, the semiconductor substrate is die-bonded to the package substrate, and the electrode portion disposed on the semiconductor substrate and the lead terminal disposed on the package substrate are wire-bonded. If the direct stretch structure is adopted, there can be considered two manufacturing processes: a procedure for applying the wire bonding after attaching the light-transmitting plate material and a procedure for applying the light-transmitting plate material after applying the wire bonding. The former procedure is preferably employed from the viewpoint of protecting the semiconductor substrate from moisture and dust. However, in the former procedure, when the translucent adhesive is applied, the translucent adhesive flows out and adheres to the electrode part, which may cause a contact failure between the electrode part and the wire.

Accordingly, the present invention provides a solid-state imaging device capable of reducing the parasitic capacitance of the floating diffusion portion while adopting a direct bonding structure in which a light-transmitting plate material and a semiconductor substrate are directly bonded with a light-transmitting adhesive. It is a first object to provide a method and such a solid-state imaging device.
Furthermore, the present invention provides a method for manufacturing a solid-state imaging device capable of preventing the light-transmitting adhesive from adhering to the electrode portion while adopting a straight-tension structure, and to provide such a solid-state imaging device. Second purpose.

  The manufacturing method of the solid-state imaging device according to the present invention includes a forming step of separately forming a light receiving portion and a floating diffusion portion on a semiconductor substrate, and a translucent adhesive on a region corresponding to the light receiving portion on the semiconductor substrate. And a bonding step of bonding a light-transmitting plate material to the semiconductor substrate with the light-transmitting adhesive applied in the coating step, and the forming step is further performed on the semiconductor substrate. In addition, a dam portion is formed to prevent the translucent adhesive applied to the region corresponding to the light receiving portion from flowing into the region corresponding to the floating diffusion portion on the semiconductor substrate.

According to the said structure, a dam part is formed in advance of application | coating of a translucent adhesive agent, and sticking of a translucent board | plate material. By forming the weir part, it is possible to prevent the translucent adhesive from flowing and covering the floating diffusion part. Accordingly, it is possible to reduce the parasitic capacitance of the floating diffusion portion while adopting a direct attachment structure in which the light transmissive plate material and the semiconductor substrate are directly attached with the light transmissive adhesive.
Further, in the forming step, the semiconductor substrate is traversed from the first edge to the second edge, and the region corresponding to the light receiving portion and the region corresponding to the floating diffusion portion are partitioned. It is good also as forming a dam part.

According to the above configuration, since the dam portion extends from the first edge portion to the second edge portion, the translucent adhesive reaches the region corresponding to the floating diffusion portion around the dam portion. Can be prevented. Furthermore, since the length of the dam portion can be made relatively long, the mechanical strength can be improved.
In the forming step, the dam portion may be formed so as to surround a region corresponding to the floating diffusion portion without surrounding a region corresponding to the light receiving portion.

According to the above configuration, since the region corresponding to the floating diffusion portion is surrounded by the dam portion, it is possible to reliably prevent the translucent adhesive from going around the dam portion and reaching the region corresponding to the floating diffusion portion. be able to.
Further, the forming step forms the dam portion so as to have a predetermined height, and the adhering step applies a translucent plate material on a translucent adhesive applied to a region corresponding to the light receiving portion. Place and press the translucent plate placed above within a period in which the translucent adhesive has fluidity until it abuts against the upper surface of the dam portion, and cure the translucent adhesive. It is good.

Since the thickness of the light-transmitting adhesive affects the light transmission characteristics, it is very important to adjust the thickness as designed. According to the said structure, the space | interval of a semiconductor substrate and a translucent board | plate material, ie, the thickness of a translucent adhesive agent, is prescribed | regulated by the height of a dam part. Therefore, the thickness of the translucent adhesive can be adjusted as designed.
Moreover, the cross section of the dam part formed in the said formation process is good also as being a rectangle or a taper shape.

According to the said structure, it can prevent as much as possible that a clearance gap will be made between a translucent adhesive agent and a dam part.
Further, in the forming step, a photosensitive material is applied onto the semiconductor substrate, and a portion that becomes a dam portion of the applied material is cured using a photolithography technique and other portions are peeled off. Thus, the dam portion may be formed.

According to the above configuration, since the weir portion can be formed without using an etching technique, it is not necessary to form an etching mask, and the manufacturing process can be simplified.
In the forming step, an etchable material is deposited on the semiconductor substrate, and an etching technique is used to leave a portion that becomes a weir portion and remove other portions. The dam portion may be formed.

According to the said structure, the room for selection of material can be expanded compared with the case where the material which has photosensitivity is used. The material that can be etched means a material in which an etchant corresponding to this material exists.
A method of manufacturing a solid-state imaging device according to the present invention includes forming a light receiving portion on a semiconductor substrate and forming a plurality of electrode portions on the semiconductor substrate apart from a region corresponding to the light receiving portion on the semiconductor substrate. A step of applying a light-transmitting adhesive to a region corresponding to the light receiving portion on the semiconductor substrate, and a light-transmitting plate material on the semiconductor substrate by the light-transmitting adhesive applied in the applying step. And the forming step further prevents the translucent adhesive applied to the region corresponding to the light receiving portion on the semiconductor substrate from flowing into the plurality of electrode portions. Forming a weir.

According to the said structure, a dam part is formed in advance of application | coating of a translucent adhesive agent, and sticking of a translucent board | plate material. By forming the weir part, it is possible to prevent the translucent adhesive from flowing and adhering to the electrode part.
In the forming step, the dam portion may be formed in an outer peripheral region of a region corresponding to the light receiving portion on the semiconductor substrate and in an inner peripheral region of the region where the plurality of electrode portions are formed. .

According to the above configuration, it is possible to prevent the translucent adhesive from reaching the electrode portion by going around the dam portion. Furthermore, since the length of the dam portion can be made relatively long, the mechanical strength can be improved.
Moreover, the dam part formed in the said formation process is good also as having a vent hole in the area | region which is not pinched | interposed into the area | region corresponding to the said light-receiving part, and these electrode parts.

  According to the said structure, when gas-permeable board | plate material is stuck, gas escapes through a vent hole, Therefore It can prevent that a clearance gap produces between a translucent adhesive agent and a translucent board | plate material. Further, since the vent hole is present in the area corresponding to the light receiving part and the area not sandwiched between the electrode parts, even if the translucent adhesive flows out through the vent hole, it does not reach the electrode part. can do.

  A solid-state imaging device according to the present invention includes a semiconductor substrate having a light receiving portion and a floating diffusion portion that is spaced apart from the light receiving portion, and a translucency applied to a region corresponding to the light receiving portion on the semiconductor substrate. A translucent plate adhered to the semiconductor substrate by an adhesive and a translucent adhesive disposed on the semiconductor substrate and applied to a region corresponding to the light receiving portion are formed in the floating diffusion portion on the semiconductor substrate. And a weir portion that prevents flow into the corresponding region.

According to the above configuration, when the weir portion is formed in advance of the application of the translucent adhesive and the pasting of the translucent board, the translucent board and the semiconductor substrate are directly pasted by the translucent adhesive. The parasitic capacitance of the floating diffusion portion can be reduced while adopting the direct pasting structure.
Moreover, the said dam part is good also as consisting of resin containing a filler.
According to the said structure, the mechanical strength of a dam part can be raised compared with the case where the filler is not contained.

  A solid-state imaging device according to the present invention includes a semiconductor substrate having a light receiving portion, a plurality of electrode portions disposed on the semiconductor substrate apart from a region corresponding to the light receiving portion on the semiconductor substrate, and the semiconductor substrate A translucent plate adhered to the semiconductor substrate by a translucent adhesive applied to a region corresponding to the light receiving portion, and a transparent plate disposed on the semiconductor substrate and applied to the region corresponding to the light receiving portion. And a weir portion that prevents the optical adhesive from flowing into the plurality of electrode portions.

According to the said structure, when a dam part is formed in advance of application | coating of a translucent adhesive agent, and sticking of a translucent board | plate material, a translucent adhesive agent flows and adheres to a several electrode part. Can be prevented.
The dam portion may be arranged in an outer peripheral region of a region corresponding to the light receiving portion on the semiconductor substrate and in an inner peripheral region of the region where the plurality of electrode portions are formed.
According to the above configuration, it is possible to prevent the translucent adhesive from reaching the electrode portion by going around the dam portion.

Moreover, the fillet which consists of the said translucent adhesive agent is good also as the side end surface of the said translucent board | plate material.
According to the said structure, the adhesiveness of a translucent board | plate material can be improved.
Moreover, the cross section of the said dam part is good also as being a rectangle or a taper shape.
According to the said structure, it can prevent as much as possible that a clearance gap will be made between a translucent adhesive agent and a dam part.

Moreover, the upper surface of the said dam part is good also as having an upward convex curved surface.
According to the above configuration, since deformation due to thermal contraction can be allowed when forming the dam portion, formation of the dam portion can be facilitated, and room for selection of the material constituting the dam portion is widened. be able to.
Moreover, the said dam part is good also as consisting of organic resin.

According to the said structure, a dam part can be easily formed on the organic film with low heat resistance laminated | stacked in order to form a color filter, a micro lens, etc.
Further, the dam portion may be made of a photosensitive material.
According to the above configuration, the dam portion can be formed without using the etching technique. Therefore, the manufacturing process can be simplified.

  A solid-state imaging device according to the present invention includes a semiconductor substrate having a light receiving portion, a plurality of electrode portions arranged on the semiconductor substrate apart from a region corresponding to the light receiving portion on the semiconductor substrate, and the semiconductor substrate And a translucent plate adhered to the semiconductor substrate via a translucent adhesive applied to a region corresponding to the light receiving portion, and the translucent plate is adhered to the semiconductor substrate. A groove portion is provided in a region other than the region facing the light receiving portion in the surface, and a part of the translucent adhesive applied to the region corresponding to the light receiving portion on the semiconductor substrate is accommodated in the groove portion. .

According to the said structure, when sticking a translucent board | plate material, an excess translucent adhesive agent is accommodated in a groove part. Therefore, it is possible to prevent the light-transmitting adhesive from flowing and adhering to the electrode portion as much as possible while adopting a direct stretch structure in which the light-transmitting plate material and the semiconductor substrate are directly bonded with the light-transmitting adhesive. it can.
Further, the plurality of electrode portions may be arranged in a row, and the groove portion of the translucent plate material may be formed along a direction in which the plurality of electrode portions are arranged.

  According to the said structure, it can prevent that a translucent adhesive agent adheres to an electrode part more effectively.

The best mode for carrying out the present invention will be described in detail with reference to the drawings.
(Embodiment 1)
<Configuration>
FIG. 1 is an exploded perspective view of the solid-state imaging device according to the first embodiment, and FIG. 2 is a plan view of the solid-state imaging device according to the first embodiment.

  As shown in FIGS. 1 and 2, the solid-state imaging device 1 includes a package substrate 10, a semiconductor substrate 20, and a translucent plate member 30. The package substrate 10 is made of ceramic or plastic and has lead terminals 11. The semiconductor substrate 20 includes a light receiving portion 21 and a floating diffusion portion 22 that is spaced apart from the light receiving portion 21 and is die-bonded to the package substrate 10. The translucent plate 30 is made of an inorganic material (such as borosilicate glass or quartz glass), an organic material (such as acrylic resin or polycarbonate resin), or a hybrid thereof, and is attached to the semiconductor substrate 20 with a translucent adhesive. ing.

  On the semiconductor substrate 20, the translucent adhesive applied to the region corresponding to the light receiving portion 21 on the semiconductor substrate 20 is prevented from flowing into the region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20. A dam portion 24 is arranged. In the first embodiment, the dam portion 24 is sandwiched between a region corresponding to the light receiving portion 21 on the semiconductor substrate 20 and a region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20, and the first edge of the semiconductor substrate 20 Extends from the portion to the second edge.

On the semiconductor substrate 20, a plurality of electrode portions 25 are further arranged apart from a region corresponding to the light receiving portion 21. The electrode portion 25 is electrically connected to the lead terminal 11 with a wire 12.
An organic film 23 for protecting the surface is further formed on the semiconductor substrate 20, but the portion of the organic film 23 corresponding to the floating diffusion portion 22 is removed.

FIG. 3 is a cross-sectional view of the solid-state imaging device according to the first embodiment.
3A shows the AA ′ cross section in the plan view of FIG. 2, and FIG. 3B shows the BB ′ cross section in the plan view of FIG.
The translucent plate 30 is attached to the semiconductor substrate 20 and the package substrate 10 via a translucent adhesive 31. The translucent adhesive 31 is applied to a region corresponding to the light receiving portion 21 on the semiconductor substrate 20, but is not applied to a region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20. That is, the floating diffusion portion 22 is not covered with the light-transmitting adhesive 31, and a gap 32 is formed between the region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20 and the light-transmitting plate member 30. As described above, since the floating diffusion portion 22 is not covered with the organic film 23 and is not covered with the translucent adhesive 31, the parasitic capacitance of the floating diffusion portion 22 is reduced.

The translucent plate 30 is disposed in contact with the upper surface of the dam portion 24. The height of the upper surface of the dam portion 24 is set so that the translucent plate 30 does not contact the loop of the wire 12.
FIG. 4 is an enlarged plan view of the semiconductor substrate 20 according to the first embodiment.
The semiconductor substrate 20 has a scribe portion 26, and a region other than the scribe portion 26 of the semiconductor substrate 20 is covered with a planarizing layer 58 made of an inorganic material. The organic film 23 covers the planarization layer 58, but the portion corresponding to the floating diffusion portion 22 and the portion corresponding to the electrode portion 25 are removed.

FIG. 5 is a partial cross-sectional view of the semiconductor substrate 20 according to the first embodiment.
FIG. 5 shows a CC ′ section and a DD ′ section in the plan view of FIG. 4.
Looking at the CC ′ cross section, the semiconductor substrate 20 has a horizontal transfer channel portion 42, a floating diffusion portion 22, a reset gate lower portion 44, and a reset drain portion 45. A first horizontal transfer electrode 51, a second horizontal transfer electrode 52, an output gate electrode 53 and a reset gate electrode 54 are formed on the semiconductor substrate 20, and these electrodes are insulated by an interlayer insulating layer 57. Yes. A planarizing layer 58 made of an inorganic material such as BPSG, BSG, or PSG is laminated on the interlayer insulating layer 57. On the planarization layer 58, planarization layers 62 and 64 made of an organic material are stacked. Note that portions of the planarization layers 62 and 64 corresponding to the floating diffusion portion 22 are removed. The dam portion 24 is formed on the planarization layer 64.

On the other hand, the semiconductor substrate 20 has a light receiving portion 21 when viewed from the DD ′ cross section. A vertical transfer electrode 55 is formed on the semiconductor substrate 20, and the electrodes are insulated by an interlayer insulating layer 57. A light shielding film 56 and a planarizing layer 58 are stacked on the interlayer insulating layer 57. On the flattening layer 58, an inner lens layer 61, a flattening layer 62, a color filter layer 63, a flattening layer 64, and a microlens 65 are laminated in this order. Each layer on the planarizing layer 58 is made of an organic material and constitutes the organic film 23.
<Manufacturing method>
FIG. 6 is a diagram illustrating a manufacturing process of the solid-state imaging device according to the first embodiment.

7 to 10 are process cross-sectional views of the solid-state imaging device according to the first embodiment.
An inorganic layer including the light receiving part 21 and the floating diffusion part 22 is formed on the semiconductor substrate 20 (FIG. 6: S11). Specifically, by adding an n-type impurity to the semiconductor substrate 20, the light receiving portion 21, the floating diffusion portion 22, the horizontal transfer channel portion 42, the floating diffusion portion 22, the reset gate lower portion 44 and the reset drain portion 45 are formed. . An interlayer insulating layer 57 is stacked on the semiconductor substrate 20, and the first horizontal transfer electrode 51, the second horizontal transfer electrode 52, the output gate electrode 53, the reset gate electrode 54, the vertical transfer electrode 55, and the light shielding film 56. Form. Thereafter, an inorganic material such as BPSG, BSG, or PSG is deposited on the semiconductor substrate 20 so as to cover the entire semiconductor substrate 20, and the planarized layer 58 is formed by reflowing it.

Next, an in-layer lens layer 61 made of an organic material is formed on the planarizing layer 58 (FIG. 6: S12).
After the intra-layer lens layer 61 is formed, a planarizing layer 62 is formed by spin-coating an organic material (FIG. 6: S13), and a color filter layer 63 made of an organic material is formed on the planarizing layer 62 (see FIG. 6). FIG. 6: S14, FIG. 7 (a)).

After the color filter layer 63 is formed, an organic material is spin-coated to form a planarization layer 64 (FIG. 6: S15, FIG. 7B), and a microlens 65 made of an organic material is formed on the planarization layer 64. (FIG. 6: S16, FIG. 8A).
Next, the portion of the organic film corresponding to the floating diffusion portion 22 is removed by etching or the like (FIG. 6: S17, FIG. 8B).

After removing the portion corresponding to the floating diffusion portion 22 of the organic film, the weir portion 24 is formed (FIG. 6: S18).
In order to form the dam portion 24, first, a resin layer 66 that covers the semiconductor substrate 20 is formed by spin-coating a resin material constituting the dam portion 24 (FIG. 9A).
Examples of the resin material constituting the weir portion 24 include acrylic, styrene, or phenol novolac-based general positive or negative photosensitive resins, and organic resins such as urethane, epoxy, and styrene. Can be used. Among these resins, by using the same photosensitive resin as that used when forming the inorganic layer and the organic film 23 and the same organic resin that constitutes the organic film 23, the number of materials can be reduced. Material management becomes easy. Further, as the material of the weir portion 24, a material in which a spherical, fiber-like or irregular-shaped filler such as resin, glass or quartz is contained in an amount of about 0% to 80% with respect to the binder resin may be used. Good. By using a resin material containing a filler, the mechanical strength of the weir portion 24 can be increased.

  The thickness of the resin layer 66 is formed such that a height h from the upper surface of the semiconductor substrate 20 to the upper surface of the resin layer 66 is equal to a predetermined interval as an interval from the upper surface of the semiconductor substrate 20 to the lower surface of the translucent plate 30. If the thickness of the resin layer 66 is about 1 to 50 μm, the resin layer 66 can be formed by one spin coating. When the thickness is more than this, the spin coating is performed a plurality of times. Further, by using spin coating, the upper surface of the semiconductor substrate 20 and the upper surface of the resin layer 66 can be made substantially parallel.

After the formation of the resin layer 66, the portion that becomes the dam portion 24 of the resin layer 66 is left, and other unnecessary portions are removed (FIG. 9B).
When the dam portion 24 is made of a photosensitive resin, the resin layer 66 is formed with the photosensitive resin, and a portion that becomes the dam portion 24 is cured by photolithography and an unnecessary portion is peeled off. For example, the rotational speed at the time of spin coating is about 1000 rpm to 3000 rpm, the prebake temperature is about 80 ° C. to 100 ° C., the exposure time is about 100 msec to 1000 msec, and the developer is an alkaline developer.

When the dam portion 24 is made of a resin that can be etched, the resin layer 66 is formed of the resin, and a mask that covers the portion that becomes the dam portion and opens the other portion is formed thereon. The portion that becomes the portion 24 is left and unnecessary portions are removed.
The processes from S11 to S18 in FIG. 6 are so-called wafer processes, and the semiconductor substrate 20 is handled in a wafer state.

Next, the wafer is diced (FIG. 6: S19), and the diced semiconductor substrate 20 is die-bonded to the package substrate 10 (FIG. 6: S20, FIG. 10A).
After the die bonding, the electrode portion 25 disposed on the semiconductor substrate 20 and the lead terminal 11 disposed on the package substrate 10 are wire-bonded (FIG. 6: S21).
After the wire bonding, a translucent adhesive 31 is applied to a region corresponding to the light receiving portion 21 on the semiconductor substrate 20 (FIG. 6: S22, FIG. 10B). As the translucent adhesive 31, for example, an epoxy adhesive that is cured at about 100 ° C. to 150 ° C., a silicone adhesive that is cured at about room temperature to 150 ° C., or the like is used. As a method for applying the translucent adhesive, for example, a dispensing method is used. In addition, a translucent adhesive shall mean the adhesive which has translucency after hardening.

  After application of the adhesive, the translucent plate 30 is attached to the semiconductor substrate 20 (FIG. 6: S23, FIG. 10 (c)). First, the translucent plate 30 is placed on the semiconductor substrate 20 to which the translucent adhesive 31 is applied, and the translucent plate 30 is attached within a period in which the translucent adhesive 31 has fluidity. Press until it contacts the upper surface of the weir 24. While pressing the translucent plate 30 or after pressing, the translucent plate 30 is shifted in the horizontal direction to adjust the horizontal position and tilt of the translucent plate 30. Note that, from the viewpoint of moisture resistance and dust resistance, the semiconductor substrate 20 is preferably sealed with the package substrate 10, the translucent plate 30, and the translucent adhesive 31. Therefore, in the application process of the translucent adhesive 31, the translucent adhesive 31 wraps around the dam portion 24 and seals the semiconductor substrate 20 when the translucent plate 30 is attached. The application amount and application location of the adhesive 31 are adjusted in advance. Care must be taken so that the translucent transparent adhesive 31 does not reach the region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20.

Thereafter, the translucent adhesive 31 is cured in a state where the translucent plate 30 is in contact with the upper surface of the weir portion 24.
As described above, in the first embodiment, since the dam portion 24 is formed, when the translucent plate 30 is attached to the semiconductor substrate 20, the region corresponding to the light receiving portion 21 on the semiconductor substrate 20 is formed. It is possible to prevent the applied translucent adhesive 31 from flowing into a region corresponding to the floating diffusion portion 22. By doing so, the sensitivity of the solid-state imaging device 1 can be increased by several% to 10%.

  Moreover, since the translucent board | plate material 30 is stuck in the state pressed until it contact | abutted to the upper surface of the dam part 24, the space | interval of the semiconductor substrate 20 and the translucent board | plate material 30, ie, the translucent adhesive agent 31, is attached. The thickness is defined by the height of the dam portion 24. Therefore, the thickness of the translucent adhesive 31 can be adjusted as designed. Note that when the upper surface of the semiconductor substrate 20 is used as a reference, the height of the upper surface of the dam portion 24 is higher than the height of the top portion of the microlens 65. Therefore, it is possible to prevent the translucent plate 30 from crushing the microlens 65 when the translucent plate 30 is positioned in the height direction.

  Further, since the upper surface of the dam portion 24 is substantially parallel to the upper surface of the semiconductor substrate 20, the translucent plate material 30 is adhered to the semiconductor substrate 20 by being attached in a state where the translucent plate material 30 is in contact with the upper surface of the dam portion 24. Can be arranged substantially in parallel. In particular, in the first embodiment, since the weir portion 24 extends from the first edge portion to the second edge portion, the length of the contact surface between the upper surface of the weir portion 24 and the translucent plate 30 is relatively long. long. Therefore, the translucent plate 30 and the semiconductor substrate 20 can be disposed substantially in parallel with relatively high accuracy. As a result, it is possible to prevent luminance unevenness (brightness shading) that occurs when the translucent plate 30 is disposed to be inclined with respect to the semiconductor substrate 20.

Moreover, since the dam part 24 is formed by a wafer process, the variation of the height of the dam part 24 for every product can be suppressed.
Further, if the weir portion 24 is formed so as to be sandwiched between the region corresponding to the light receiving portion 21 on the semiconductor substrate 20 and the region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20, the position is slightly shifted. Can also achieve the object of the present invention. Therefore, a mask having a relatively low rank can be adopted as a mask for forming the dam portion 24, and the time required for positioning by the stepper can be shortened.

In addition, by adopting a direct attachment structure in which the light transmissive plate 30 and the semiconductor substrate 20 are directly attached via the light transmissive adhesive 31, the size of the entire solid-state imaging device 1 can be reduced. . Furthermore, it is possible to prevent deterioration of the shape, transparency, and refractive index of the microlens 65 (particularly when formed of an organic material) due to changes in the surrounding environment (particularly humidity).
The first embodiment is preferably used when the distance from the end of the semiconductor substrate 20 to the end of the package substrate 10 is larger than 250 μm.
(Embodiment 2)
FIG. 11 is a plan view of the solid-state imaging device according to the second embodiment.

In the second embodiment, the dam portion 24 surrounds the region corresponding to the light-receiving portion 21 on the semiconductor substrate 20 and the region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20 without surrounding the electrode portion 25. Further, the size of the package substrate 10 of the second embodiment is smaller than the size of the package substrate 10 of the first embodiment.
FIG. 12 is a cross-sectional view of the solid-state imaging device according to the second embodiment.

12A shows the EE ′ cross section in the plan view of FIG. 11, and FIG. 12B shows the FF ′ cross section in the plan view of FIG.
FIG. 13 is an enlarged plan view of the semiconductor substrate 20 according to the second embodiment.
In the second embodiment, the dam portion 24 surrounds a region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20. The translucent plate 30 is stuck in contact with the upper surface of the weir portion 24. A space 32 is formed in a region surrounded by the weir part 24.

  As described above, in the second embodiment, since the dam portion 24 is formed so as to surround the region corresponding to the floating diffusion portion 22, when the translucent plate 30 is attached to the semiconductor substrate 20, the semiconductor It is possible to reliably prevent the translucent adhesive 31 applied to the region corresponding to the light receiving portion 21 on the substrate 20 from flowing into the region corresponding to the floating diffusion portion 22. Therefore, the sensitivity of the solid-state imaging device 1 can be improved.

The second embodiment is preferably used when the size of the semiconductor substrate 20 and the package substrate 10 are substantially the same, or when the distance from the end of the semiconductor substrate 20 to the end of the package substrate 10 is within 200 μm.
(Embodiment 3)
FIG. 14 is a plan view of the solid-state imaging device according to the third embodiment.

  In the third embodiment, the dam portion 24 surrounds a region corresponding to the light receiving portion 21 on the semiconductor substrate 20 and a region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20 without surrounding the electrode portion 25. Further, the size of the package substrate 10 of the third embodiment is smaller than the size of the package substrate 10 of the first embodiment and larger than the size of the package substrate 10 of the second embodiment.

FIG. 15 is a cross-sectional view of the solid-state imaging device according to the third embodiment.
FIG. 15A shows a GG ′ cross section in the plan view of FIG. 14, and FIG. 15B shows a HH ′ cross section in the plan view of FIG. 14.
FIG. 16 is an enlarged plan view of the semiconductor substrate 20 according to the third embodiment.
In the third embodiment, the dam portion 24 surrounds a region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20. As shown in FIG. 16, the dam portion 24 includes two portions 24a and 24b having different heights. The translucent plate 30 is stuck in a state where it is in contact with a part of the upper surface of the weir 24 (part 24a). A space 32 is formed in a region surrounded by the weir part 24.

Thus, in Embodiment 3, since the translucent plate 30 is brought into contact with the portion 24a of the dam portion 24 and is not brought into contact with the portion 24b, the accuracy of the height of the portion 24b can be lowered. Therefore, the manufacturing cost can be reduced.
The third embodiment is preferably used when the distance from the end of the semiconductor substrate 20 to the end of the package substrate 10 is about 200 to 250 μm.
(Embodiment 4)
<Configuration>
FIG. 17 is a plan view of the solid-state imaging device according to the fourth embodiment.

FIG. 18 is a cross-sectional view of the solid-state imaging device according to the fourth embodiment.
FIG. 18 shows a JJ ′ cross section in the plan view of FIG.
In the fourth embodiment, the dam portion 24 is the outer peripheral region of the region corresponding to the light receiving portion 21 on the semiconductor substrate 20, and the region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20 and the electrode portion 25 are formed. It is formed in the inner peripheral area of the area. Further, the dam portion 24 is not sandwiched between the region corresponding to the light receiving portion 21 on the semiconductor substrate 20 and the region corresponding to the floating diffusion portion 22 on the semiconductor substrate 20, and corresponds to the light receiving portion 21 on the semiconductor substrate 20. A vent hole 27 is provided in a region that is not sandwiched between the region to be operated and the electrode portion 25.

  With such a configuration, when the translucent plate 30 is attached, gas escapes through the air holes 27, so that no bubbles are generated on the region corresponding to the light receiving unit 21. Further, since the air holes 27 are not sandwiched between the region corresponding to the light receiving portion 21 and the region corresponding to the floating diffusion portion 22 and are present in the region not corresponding to the region corresponding to the light receiving portion 21 and the electrode portion 25. Even if the translucent adhesive 31 flows out through the vent hole 27, it can be prevented from reaching the region corresponding to the floating diffusion portion 22 or the electrode portion 25.

FIG. 19 is a plan view of a solid-state imaging device according to a modification.
As shown in FIG. 19, the electrode portion 25 is arranged so as to make a round around the peripheral edge of the semiconductor substrate 20. Also in this example, the weir portion 24 is not sandwiched between the region corresponding to the light receiving portion 21 and the region corresponding to the floating diffusion portion 22, and is not sandwiched between the region corresponding to the light receiving portion 21 and the electrode portion 25. A vent hole 27 is provided. Therefore, the same effect as described above is obtained.
<Manufacturing method>
FIG. 20 is a diagram illustrating a manufacturing process of the solid-state imaging device according to the fourth embodiment.

  In the fourth embodiment, the adhesive application step (FIG. 20: S39) and the translucent plate attaching step (FIG. 20: S40) are the dicing step (FIG. 20: S41) and the die bonding step (FIG. 20: S42). And before the wire bonding step (S20: S43). Thus, the effect which protects the semiconductor substrate 20 from moisture and dust can be heightened by sticking the translucent board | plate material 30 early. The details of each of the above steps are the same as those in the first embodiment, and a description thereof will be omitted.

FIG. 21 is a process cross-sectional view of the solid-state imaging device according to the fourth embodiment.
FIG. 21A shows a semiconductor substrate separated by a dicing process. FIG. 21B shows the package substrate 10 prepared in the die bonding process. FIG. 21C shows a solid-state imaging device obtained through a die bonding process and a wire bonding process.
(Embodiment 5)
FIG. 22 is a plan view of the solid-state imaging device according to the fifth embodiment.

FIG. 23 is a cross-sectional view of the solid-state imaging device according to the fifth embodiment.
FIG. 23 shows a KK ′ cross section in the plan view of FIG. In the fifth embodiment, the translucent plate 30 is attached to the semiconductor substrate 20 without being in contact with the upper surface of the dam portion 24, and the translucent adhesive 31 is applied to the side end surface of the translucent plate 30. A fillet 33 is formed. Since the translucent plate 30 is not in contact with the upper surface of the dam portion 24, it is assumed that a gap is generated between the translucent plate 30 and the translucent adhesive 31 when the translucent plate 30 is attached. In addition, the gap can be eliminated by pressing the translucent plate 30. Furthermore, the adhesiveness of the translucent board | plate material 30 can be improved because the fillet 33 is formed.
(Embodiment 6)
FIG. 24 is a cross-sectional view of the solid-state imaging device according to the sixth embodiment.

In the sixth embodiment, the upper surface of the dam portion 24 has an upwardly convex curved surface. Therefore, since deformation due to thermal contraction can be allowed when the dam portion 24 is formed, formation of the dam portion can be facilitated, and the room for selecting the material constituting the dam portion can be expanded. .
(Embodiment 7)
FIG. 25 is a cross-sectional view of the solid-state imaging device according to the seventh embodiment.

In the seventh embodiment, the dam portion 24 has a double structure including an inner dam 24c and an outer dam 24d. Therefore, even when the translucent plate 30 is stuck, even if the translucent adhesive 31 flows out beyond the inner weir 24c, it can be blocked by the outer weir 24d.
(Embodiment 8)
FIG. 26 is a plan view of the solid-state imaging device according to the eighth embodiment.

FIG. 27 is a cross-sectional view of the solid-state imaging device according to the eighth embodiment.
27 shows an LL ′ cross section in the plan view of FIG.
In the eighth embodiment, the translucent plate 30 has a groove 34 in a region other than the region facing the light receiving unit 21 in the plane adhered to the semiconductor substrate 20, and the light receiving unit 21 on the semiconductor substrate 20 has A part of the translucent adhesive 31 applied to the corresponding region is accommodated in the groove 34. Thus, if the groove part 34 is formed in the translucent board | plate material 30, when sticking the translucent board | plate material 30 to the semiconductor substrate 20, the excess translucent adhesive agent 31 will be accommodated in the groove part 34. FIG. . Therefore, it is possible to prevent the translucent adhesive 31 from adhering to the electrode portion 25 while adopting a direct stretch structure in which the translucent plate material 30 and the semiconductor substrate 20 are directly adhered by the translucent adhesive 31. Can do.

Moreover, since the groove part 34 is formed along the direction where the electrode part 25 is arranged, it can prevent that a translucent adhesive agent adheres to an electrode part more effectively.
In this example, the cross-sectional shape of the groove 34 is rectangular, but the present invention is not limited to this, and the cross-sectional shape of the groove 34 may be curved as shown in FIG.
Although the solid-state imaging device according to the present invention has been described based on the embodiments, the present invention is not limited to these embodiments. For example, the following modifications can be considered.
(1) In the first embodiment, the dam portion 24 extends from the first edge portion of the semiconductor substrate 20 to the second edge portion. However, the present invention is not limited to this as long as the weir portion 24 is formed on the semiconductor substrate 20 at least between the light receiving portion 21 and the floating diffusion portion 22. For example, it may be interrupted halfway without extending to the edge of the semiconductor substrate 20. At this time, the extent to which the light-transmitting adhesive 31 extends is determined by the viscosity and application amount of the light-transmitting adhesive 31 and the weir portion so as to achieve the purpose of preventing the light-transmitting adhesive 31 from flowing to the floating diffusion portion 22. 24 is designed in consideration of the position and height of 24, the relative positional relationship between the light receiving unit 21 and the floating diffusion unit 22, and the like.
(2) In the first embodiment, the dam portion 24 is formed after the layers (61 to 65) constituting the organic film 23 are formed. However, the present invention is not limited to this, and the dam portion 24 may be formed at any stage. However, when each layer constituting the organic film 23 is formed by spin coating, as shown in the first embodiment, it is desirable to form the dam portion 24 after forming each layer constituting the organic film 23. .
(3) In the first embodiment, the planar shape of the weir portion 24 is a shape bent substantially at a right angle. Moreover, in Embodiment 2 and Embodiment 3, the planar shape of the dam portion 24 is a quadrangular shape. However, the present invention is not limited to this as long as the translucent adhesive 31 can be prevented from flowing to the floating diffusion portion 22. For example, the planar shape of the dam portion 24 may be a circular shape or a polygonal shape. Moreover, the shape which combined the shape of Embodiment 1 and the shape of Embodiment 2 may be sufficient.
(4) In the embodiment, the cross-sectional shape of the weir portion 24 is rectangular. However, the present invention is not limited to this, and may be trapezoidal, inverted trapezoidal, or the like.
(5) In any of the embodiments, the weir portion 24 may be shared with a dummy pattern formed for other purposes. For example, the dummy pattern for forming a uniform thin film on the microlens and the weir portion 24 can be shared.

  The solid-state imaging device according to the present invention can be used for a digital camera, for example.

1 is an exploded perspective view of a solid-state imaging device according to Embodiment 1. FIG. 2 is a plan view of the solid-state imaging device according to Embodiment 1. FIG. 2 is a cross-sectional view of the solid-state imaging device according to Embodiment 1. FIG. 2 is an enlarged plan view of a semiconductor substrate 20 according to the first embodiment. FIG. 1 is a partial cross-sectional view of a semiconductor substrate 20 according to a first embodiment. 6 is a diagram illustrating a manufacturing process of the solid-state imaging device according to Embodiment 1. FIG. 6 is a process cross-sectional view of the solid-state imaging device according to Embodiment 1. FIG. 6 is a process cross-sectional view of the solid-state imaging device according to Embodiment 1. FIG. 6 is a process cross-sectional view of the solid-state imaging device according to Embodiment 1. FIG. 6 is a process cross-sectional view of the solid-state imaging device according to Embodiment 1. FIG. 6 is a plan view of a solid-state imaging device according to Embodiment 2. FIG. 6 is a cross-sectional view of a solid-state imaging device according to Embodiment 2. FIG. 4 is an enlarged plan view of a semiconductor substrate 20 according to a second embodiment. FIG. 6 is a plan view of a solid-state imaging device according to Embodiment 3. FIG. 6 is a cross-sectional view of a solid-state imaging device according to Embodiment 3. FIG. FIG. 6 is an enlarged plan view of a semiconductor substrate 20 according to a third embodiment. 6 is a plan view of a solid-state imaging apparatus according to Embodiment 4. FIG. 6 is a cross-sectional view of a solid-state imaging device according to Embodiment 4. FIG. It is a top view of the solid-state imaging device concerning a modification. FIG. 10 is a diagram illustrating a manufacturing process of the solid-state imaging device according to the fourth embodiment. FIG. 10 is a process cross-sectional view of the solid-state imaging device according to the fourth embodiment. 6 is a plan view of a solid-state imaging device according to Embodiment 5. FIG. FIG. 9 is a cross-sectional view of a solid-state imaging device according to a fifth embodiment. FIG. 9 is a cross-sectional view of a solid-state imaging device according to a sixth embodiment. FIG. 10 is a cross-sectional view of a solid-state imaging device according to a seventh embodiment. FIG. 10 is a plan view of a solid-state imaging device according to an eighth embodiment. FIG. 10 is a cross-sectional view of a solid-state imaging device according to an eighth embodiment. It is sectional drawing of the translucent board | plate material which concerns on a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solid-state imaging device 10 Package substrate 11 Lead terminal 12 Wire 20 Semiconductor substrate 21 Light-receiving part 22 Floating diffusion part 23 Organic film 24 Weir part 25 Electrode part 26 Scribe part 27 Vent hole 30 Translucent plate material 31 Translucent adhesive agent 32 Space | gap 33 Fillet 34 Groove 42 Horizontal Transfer Channel 44 Lower Reset Gate 45 Reset Drain 51 Horizontal Transfer Electrode 52 Horizontal Transfer Electrode 53 Output Gate Electrode 54 Reset Gate Electrode 55 Vertical Transfer Electrode 56 Light-shielding Film 57 Interlayer Insulating Layer 58 Flattening Layer 61 Layer Inner lens layer 62 Flattening layer 63 Color filter layer 64 Flattening layer 65 Microlens 66 Resin layer

Claims (25)

Forming a light receiving portion and a floating diffusion portion separately on a semiconductor substrate;
An application step of applying a translucent adhesive to a region corresponding to the light receiving portion on the semiconductor substrate;
A pasting step of pasting a translucent plate to the semiconductor substrate by the translucent adhesive applied in the coating step,
The forming step further includes a weir portion for preventing the translucent adhesive applied to the region corresponding to the light receiving portion on the semiconductor substrate from flowing into the region corresponding to the floating diffusion portion on the semiconductor substrate. Forming a solid-state imaging device. In the forming step, the dam portion is traversed from the first edge portion to the second edge portion of the semiconductor substrate, and partitions the region corresponding to the light receiving portion and the region corresponding to the floating diffusion portion. The method of manufacturing a solid-state imaging device according to claim 1, wherein: 2. The solid-state imaging device according to claim 1, wherein the forming step forms the dam portion so as not to surround a region corresponding to the light receiving portion but to surround a region corresponding to the floating diffusion portion. Manufacturing method. In the forming step, the weir portion is formed to have a predetermined height,
In the attaching step, the translucent plate material is placed on the translucent adhesive applied to the region corresponding to the light receiving unit, and the translucent adhesive is placed in a period in which the translucent adhesive has fluidity. The method of manufacturing a solid-state imaging device according to claim 1, wherein the translucent plate material is pressed until it comes into contact with the upper surface of the dam portion to cure the translucent adhesive. The method for manufacturing a solid-state imaging device according to claim 1, wherein a cross section of the dam portion formed in the forming step is rectangular or tapered. In the forming step, a material having photosensitivity is applied onto the semiconductor substrate, and a portion that becomes a weir portion is cured using a photolithography technique, and other portions are peeled off. The method of manufacturing a solid-state imaging device according to claim 1, wherein the dam portion is formed. In the forming step, an etchable material is deposited on the semiconductor substrate, and an etching technique is used to leave a portion that becomes a dam portion and remove other portions by removing the remaining portion. The method for manufacturing the solid-state imaging device according to claim 1, wherein a dam portion is formed. Forming a light receiving portion on the semiconductor substrate and forming a plurality of electrode portions on the semiconductor substrate apart from a region corresponding to the light receiving portion on the semiconductor substrate;
An application step of applying a translucent adhesive to a region corresponding to the light receiving portion on the semiconductor substrate;
A pasting step of pasting a translucent plate to the semiconductor substrate by the translucent adhesive applied in the coating step,
The forming step further includes forming a weir portion on the semiconductor substrate for preventing a translucent adhesive applied to a region corresponding to the light receiving portion from flowing into the plurality of electrode portions. A method for manufacturing a solid-state imaging device. The said formation process forms the said dam part in the outer peripheral area | region of the area | region corresponding to the said light-receiving part, and the inner peripheral area | region of the area | region in which the said several electrode part was formed. Manufacturing method of solid-state imaging device. 10. The solid-state imaging device according to claim 9, wherein the dam portion formed in the forming step has a vent hole in a region not sandwiched between a region corresponding to the light receiving unit and the plurality of electrode units. Production method. In the forming step, the weir portion is formed to have a predetermined height,
In the attaching step, the translucent plate material is placed on the translucent adhesive applied to the region corresponding to the light receiving unit, and the translucent adhesive is placed in a period in which the translucent adhesive has fluidity. The method for manufacturing a solid-state imaging device according to claim 8, wherein the translucent plate material is pressed until it comes into contact with the upper surface of the dam portion to cure the translucent adhesive. The method for manufacturing a solid-state imaging device according to claim 8, wherein a cross section of the dam portion formed in the forming step is rectangular or tapered. In the forming step, a material having photosensitivity is applied onto the semiconductor substrate, and a portion that becomes a weir portion is cured using a photolithography technique, and other portions are peeled off. The method of manufacturing a solid-state imaging device according to claim 8, wherein the dam portion is formed. In the forming step, an etchable material is cured on the semiconductor substrate, and a portion that becomes a dam portion of the deposited material is left using an etching technique and other portions are removed, The method for manufacturing a solid-state imaging device according to claim 8, wherein a dam portion is formed. A semiconductor substrate having a light receiving portion and a floating diffusion portion spaced apart from the light receiving portion;
A translucent plate adhered to the semiconductor substrate by a translucent adhesive applied to a region corresponding to the light receiving portion on the semiconductor substrate;
A weir portion disposed on the semiconductor substrate and preventing a translucent adhesive applied to a region corresponding to the light receiving portion from flowing into a region corresponding to the floating diffusion portion on the semiconductor substrate. A solid-state imaging device. The solid-state imaging device according to claim 15, wherein the dam portion is made of a resin containing a filler. A semiconductor substrate having a light receiving portion;
A plurality of electrode portions disposed on the semiconductor substrate apart from a region corresponding to the light receiving portion on the semiconductor substrate;
A translucent plate adhered to the semiconductor substrate by a translucent adhesive applied to a region corresponding to the light receiving portion on the semiconductor substrate;
A solid-state imaging device comprising: a weir portion disposed on the semiconductor substrate and preventing a translucent adhesive applied to a region corresponding to the light receiving portion from flowing into the plurality of electrode portions. The dam portion is arranged in an outer peripheral region of a region corresponding to the light receiving portion on the semiconductor substrate and in an inner peripheral region of the region where the plurality of electrode portions are formed. The solid-state imaging device described. The solid-state imaging device according to claim 17, wherein a fillet made of the translucent adhesive is formed on a side end surface of the translucent plate member. The solid-state imaging device according to claim 17, wherein a cross section of the dam portion is rectangular or tapered. 18. The solid-state imaging device according to claim 17, wherein an upper surface of the dam portion has an upwardly convex curved surface. The solid-state imaging device according to claim 17, wherein the dam portion is made of an organic resin. The solid-state imaging device according to claim 22, wherein the dam portion is made of a photosensitive material. A semiconductor substrate having a light receiving portion;
A plurality of electrode portions disposed on the semiconductor substrate apart from a region corresponding to the light receiving portion on the semiconductor substrate;
A translucent plate adhered to the semiconductor substrate via a translucent adhesive applied to a region corresponding to the light receiving portion on the semiconductor substrate;
The translucent plate member has a groove in a region other than a region facing the light receiving unit in a plane adhered to the semiconductor substrate, and is applied to a region corresponding to the light receiving unit on the semiconductor substrate. A solid-state imaging device, wherein a part of the optical adhesive is accommodated in the groove. The plurality of electrode portions are arranged in a row,
The solid-state imaging device according to claim 24, wherein the groove portion of the translucent plate material is formed along a direction in which the plurality of electrode portions are arranged.

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