WO2003096427A1 - Rear surface irradiation photodiode array and method for producing the same - Google Patents

Abstract

Both electrodes of the anode and cathode of a photodiode in a semiconductor substrate (1) are collected at one side thereof. This is achieved by leading one electrode electrically to the other side through a hole H penetrating the semiconductor substrate (1) and the time required for boring the hole H is shortened because the semiconductor substrate (1) has been made thin by polishing. Since a supporting substrate (3) is attached to the semiconductor substrate (1) in order to reinforce the thinned substrate during production process, handling of the wafer is facilitated during process resulting in a photodiode suitable for mass production.

Description

 Itoda »

Backside illuminated photodiode array and method of manufacturing the same

Technical field

 The present invention relates to a back-illuminated photodiode array and a method for manufacturing the same.

Background art

 Three-dimensional packaging technology has been studied in many fields. Conventionally, in three-dimensional mounting, a hole penetrating the upper and lower surfaces of a substrate is formed, and an electrode on one side is drawn out to the other side through the hole.

Disclosure of the invention

 However, in the through-hole forming process in such three-dimensional mounting, ICP plasma etching is usually used, but the thickness of the wafer is 300 μπ! Since it is as thick as about 400 / i i, it takes a lot of time to form a through hole. In addition, since the etching process using the ICP plasma etching apparatus is performed once per wafer Z, it is impossible to process a plurality of wafers at the same time. As a result, a through hole is formed per wafer. Requires a lot of time. Therefore, if such an etching technique is used, a product that can form only a small amount of products by one etching, that is, a large-area photodiode array cannot be mass-produced industrially. For example, even if it takes several hours per wafer to form a hole and several large-area photodiode arrays are formed, it is not industrially feasible.

 The present invention has been made in view of such problems, and has as its object to provide a back-illuminated photodiode array that can be mass-produced and a method for manufacturing the same.

In order to solve the above-mentioned problems, a method for manufacturing a back-illuminated photodiode array according to the present invention includes: (a) a step of forming a high-concentration impurity region on one surface side of a semiconductor substrate; (C) polishing the other surface of the semiconductor substrate to reduce the thickness of the semiconductor substrate; and (d) polishing the other surface of the semiconductor substrate to reduce the thickness of the semiconductor substrate. Side with a high concentration impurity region and multiple photodiodes (E) forming a hole from the high-concentration impurity region on the other surface side of the semiconductor substrate to reach the high-concentration impurity region on the one surface side; and (f) the one-side surface. Electrically connecting the high-concentration impurity region on the other surface side through the hole, and (g) removing the support substrate after the step (f). . One of the anode and the power source of the photodiode is located on one side or the other side of the semiconductor substrate, and the other is located on the remaining side.

 According to this manufacturing method, the photodiode array is thinned by the polishing process, so that the time for forming the holes is reduced, and the high-concentration impurity regions formed on both sides of the semiconductor substrate are connected through the holes. Therefore, the anode and the power source of the photodiode can be electrically led to the same surface (the other surface) of the semiconductor substrate. The problem related to the reduction of the substrate strength due to the thin film bonding and further to the problem of wafer breakage can be reinforced because the support substrate is provided on one side of the semiconductor substrate during wafer production. According to this invention, a photodiode array having a plurality of photodiodes can be mass-produced for the first time in the industry. Further, since the photodiode array is of the back-illuminated type, it has a high signal-to-noise ratio and can be used for a highly accurate photodetector.

 The semiconductor substrate and the high-concentration impurity region are of a first conductivity type (for example, n-type), and the plurality of photodiodes are composed of a plurality of second conductivity type (for example,!) Impurity regions and a semiconductor substrate. The anode or the force sword located on the one surface side of any of the photodiodes may be electrically guided to the other surface side.

 Further, when a step of forming a first-conductivity-type full-surface impurity semiconductor layer shallower than the high-concentration impurity region on the entire surface on one surface side of the semiconductor substrate, the whole-surface impurity semiconductor layer functions as an accumulation layer.

In the case where a step of forming an oxide film on one surface side of the semiconductor substrate is provided, This can function as a protective film.

 Further, the method of manufacturing a back-illuminated photodiode array of the present invention is characterized by further comprising a step of embedding a resin in the hole. By embedding resin in the holes, the strength of the semiconductor substrate can be improved.

 A step of applying a photoresist as the resin to the entire surface on the other surface side of the semiconductor substrate; and a step of forming an electrode on the other surface side of the semiconductor substrate. It is preferable that the method further includes a step of removing only the photoresist and a step of forming an electrode in a region from which the photoresist has been removed. In this case, the resin can be embedded by an ordinary photolithography process using a small resist, and the electrodes can be exposed by the photoresist.

 Further, from the viewpoint of three-dimensional mounting, the above-described method for manufacturing a back-illuminated photodiode array includes a step of forming a bump on the other surface of the semiconductor substrate so that an anode and a cathode of the photodiode are electrically connected to a circuit board. It is preferable that the method further includes a step of attaching to the circuit board via In this case, the anode of the photodiode and the connection wiring of the force sword electrically connected to the circuit board by the bump can extend in the direction of the circuit board, that is, in the thickness direction of the semiconductor substrate, so that the mounting area can be reduced. That is, since the dead space is reduced in the plane direction, a plurality of back-illuminated photodiode arrays can be arranged in the lateral direction (two-dimensionally) of the semiconductor substrate. Can be provided.

 This large-area back-illuminated photodiode array can be applied to computer tomography (CT) and positron emission tomography (PET) equipment by combining it with a scintillator that converts X-rays and τ-rays into visible light. can do.

Further, the back-illuminated photodiode array of the present invention can be manufactured by the above-described method, and the high concentration impurity region is formed on one side and the other side of the semiconductor substrate. In a back-illuminated photodiode array, each of which is selectively connected to a photodiode node and a force source formed on the other surface side of the semiconductor substrate, the high-concentration impurity regions make the semiconductor substrate thick. It is electrically connected via a hole penetrating in the direction, and the hole is filled with a resin. This backside illuminated photodiode array has advantages in three-dimensional mounting and manufacturing method, and the resin in the holes can suppress a decrease in substrate strength of the backside illuminated photodiode.

 The semiconductor substrate and the high-concentration impurity region are of a first conductivity type, and a photodiode formed on the other surface side of the semiconductor substrate includes a second conductivity-type impurity region and a semiconductor substrate. It is preferable to provide a first-conductivity-type full-surface impurity semiconductor layer shallower than the high-concentration impurity region on the entire surface on one side of the semiconductor substrate.

In this case, the entire impurity semiconductor layer can function as an accumulation layer, and high-performance detection can be performed.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A is an explanatory diagram for explaining a method of manufacturing a back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 1B is an explanatory diagram for explaining the method for manufacturing the back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 1C is an explanatory diagram for explaining the manufacturing method of the back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 1D is an explanatory diagram for explaining the manufacturing method of the back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 1E is an explanatory diagram for explaining the manufacturing method of the back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 1F is an explanatory diagram for explaining the method for manufacturing the back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 1G is an explanatory diagram for explaining the manufacturing method of the back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 1H is an explanatory diagram for explaining the method for manufacturing the back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 1I is an explanatory diagram for explaining the manufacturing method of the back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 1J is an explanatory diagram for explaining the manufacturing method of the back-illuminated photodiode array according to the embodiment, and shows a vertical cross-sectional configuration of the back-illuminated photodiode array. FIG. 2 is an explanatory diagram of an imaging apparatus including a plurality of back-illuminated photodiode arrays PDA shown in FIG.

BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, the backside illuminated photodiode array according to the embodiment will be described. Note that the same reference numerals are used for the same elements, and duplicate descriptions are omitted.

 1A to 1J are explanatory views for explaining a method of manufacturing the back-illuminated photodiode array according to the embodiment, and show a vertical cross-sectional configuration of the back-illuminated photodiode array. The details are described below.

 In this manufacturing method, the following steps (1) to (10) are sequentially performed.

 Process (1)

First, a semiconductor substrate (wafer) 1 made of Si is prepared. The conductivity type of the semiconductor substrate 1 is n-type, and the specific resistance is about lkΩ ■ cm. The specific resistance of the semiconductor substrate 1 is set in consideration of the balance between low capacitance, low noise, and high-speed response. Next, on the back surface (one surface side) of the semiconductor substrate 1, a plurality of n-type high-concentration impurity regions In having a thickness of a predetermined number / space are formed (FIG. 1A). Here, the “back surface” is a light incident surface of a back-illuminated photodiode that is finally manufactured, and is a rule used for convenience of description, and is not a lower surface of the drawing. I want to. The high-concentration impurity region In is n-type and is formed by diffusion of phosphorus. 10 ¹⁷ cm—means a region with a carrier concentration of ³ or more.

 Process (2)

Next, a thin impurity semiconductor 1nc is formed on the entire back surface of the semiconductor substrate 1 (FIG. 1B). The conductivity type of the impurity semiconductor layer 1nc is n-type, and the impurity concentration is high. The impurity used in this formation step is arsenic, and the depth of the ion implantation is set to be smaller than the diffusion depth of phosphorus, so that the depth becomes shallow (0.1 πι or less). The method for forming this layer is an ion implantation method. For example, the implantation energy is 80 kev and the dose is 2 × 10 ¹⁵ cm− ² . Since the depth of this layer is shallow, the sensitivity of the photodetector is high.

 Process (3)

 Next, an oxide film 2 is formed on the rear surface side of the semiconductor substrate 1 by thermal oxidation (FIG. 1C). Process (4)

 Further, the support substrate 3 is bonded to the back surface of the semiconductor substrate 1 (FIG. 1D). The material of the support substrate 3 does not need to be a special material because it is removed in a later step as described later. For example, p-type silicon of several tens Ω · cm, which is generally available, is used. In the bonding step, the supporting substrate 3 is pressed against the semiconductor substrate 1 via the oxide film 2 and bonded by applying heat of 100 ° C. or less.

 Process (5)

 Thereafter, the support substrate 3 is polished from the front side (the side opposite to the back side: the other side) to thin the semiconductor substrate 1 to a predetermined thickness (FIG. 1E). The thickness of the semiconductor substrate 1 after this mirror polishing step is, for example, several tens μπι to 150 / im, and preferably about 50 μπη to 100 m.

 Process (6)

Next, a plurality of n-type high-concentration impurity regions I n ′ and a plurality of p-type impurity regions 1 P separated by a predetermined distance are formed on the surface side of the semiconductor substrate 1, and further, the surface side of the semiconductor substrate 1 is thermally oxidized. An oxide film (S i 0 ₂ ) 4 is formed (FIG. 1F). n-type high concentration impurity region Region I n 'is formed by diffusing phosphorus. The ί> type impurity region lp is formed by diffusing or implanting boron into the substrate. The P-type impurity region 1 P forms a PN junction with the n-type semiconductor substrate 1 to form a photodiode. This photodiode is located on the front surface side of the semiconductor substrate 1. The photodiode can be an avalanche photodiode or a PIN photodiode.

 Process (7)

 Next, a hole H reaching the back side from the front side of the semiconductor substrate 1 is formed (FIG. 1G). The hole H is formed by using the oxide film 4 on the surface side of the semiconductor substrate 1 to form a mask having an opening on the high-concentration impurity region 1 n ′, and etching the surface of the semiconductor substrate 1 through the mask. By doing. At the time of etching, the oxide film 4 can be patterned by photolithography so that the oxide film 4 is used as a mask. For this etching, isotropic wet etching can be used, and isotropic dry etching such as atmospheric pressure plasma etching (ADP) can also be used. H F ZHN Og or the like can be used as an etchant for wet etching.

 If such an etching method is used, not only etching with relatively high productivity can be performed, but also the shape of the hole H becomes a mortar shape, that is, a tapered shape, so that step coverage in the subsequent electrode formation is improved. . The exposed side of the high-concentration impurity region 1 n ′ on the front surface side of the semiconductor substrate 1 and the exposed side surface of the high-concentration impurity region 1 n on the back surface and the etched side surface of the semiconductor substrate 1 constitute the inner surface of the hole H. Will be done.

 Process (8)

Further, an n-type impurity is added into the semiconductor substrate 1 from the side surface of the hole H to electrically connect the n-type high-concentration impurity region 1 n ′ on the front surface and the n-type high-concentration impurity region 1 n on the back surface. (Fig. 1H). This impurity added region is indicated by reference numeral h1. This impurity addition step The ion implantation or diffusion of the n-type impurity is performed from the surface side of the semiconductor substrate 1 with the mask left or with the oxide film 4 as a mask. Process (9)

 Next, in order to reduce the series resistance, a metal electrode film h2 made of aluminum is formed on the inner surface of the hole H. This forms a force sword common electrode and extends to the surface of the semiconductor substrate 1. If the oxide film 4 is patterned so that the surface of the p-type impurity region 1 p of the semiconductor substrate 1 is exposed before the formation of the metal electrode film h 2, the p-type impurity region 1 p is formed simultaneously with the metal electrode film h 2. Can be formed. Thereafter, a photosensitive resin (photoresist such as polyimide) R is applied on the surface of the semiconductor substrate 1 so as to fill the inner surface of the hole H, and a metal electrode made of aluminum is formed by a photolithography process. Expose. Further, Ni and Au are sequentially plated on the exposed metal electrode portion, thereby forming an electrode OM on the photodiode array.

 Finally, the support substrate 3 is completely removed by grinding and dry etching to expose the oxide film 2 serving as a light incident surface.

 Next, by cutting the chip into a predetermined chip size by dicing, a back-illuminated photodiode array having an electrode on only one surface side (the other surface side) of the semiconductor substrate is completed (FIG. 11).

 Process (10)

The photodiode array chip is arranged upside down, that is, in such a manner that the front side of the semiconductor substrate 1 is located on the circuit board C side and the light incident surface is the back side. That is, the semiconductor substrate 1 is placed on the circuit board C via bumps B made of Au or solder, and the bumps B electrically connect the photodiode electrodes OM to the wiring on the circuit board C (see FIG. 1 J). The cathode of the photodiode, that is, the n-type semiconductor substrate 1 and the n-type high-concentration impurity region 1 n are connected to the electrode OM located on the surface side of the semiconductor substrate 1 via the metal electrode film h2 and the impurity-doped region h1. ing. The anode of the photodiode, that is, the P-type impurity region 1 P is It is connected to the polar membrane h2 and the electrode ΔM. These electrodes are connected to the power source wiring and the anode wiring of the circuit board C via the bumps B, respectively.

 As described above, the method of manufacturing the back-illuminated photodiode array described above includes: (a) forming a high-concentration impurity region 1 n on one surface (back surface) of the semiconductor substrate 1; (C) bonding the support substrate 3 to the back surface of the semiconductor substrate 1; (c) polishing the other surface (front surface) of the semiconductor substrate 1 to thin the semiconductor substrate 1; (E) forming a high-concentration impurity region 1 n ′ and a plurality of photodiodes on the front surface of the semiconductor substrate 1; (F) electrically connecting the high-concentration impurity regions I n and In ′ on the back side and the front side via the hole H; and (g) forming the step (g). removing the supporting substrate 3 after f). One of the anode and the power source of the photodiode is located on one of the one surface side and the other surface side of the semiconductor substrate, and the other is located on the remaining surface side.

 According to this manufacturing method, the photodiode array, that is, the semiconductor substrate 1 is thinned to a predetermined thickness by the polishing step, so that the time for forming the hole H is shortened, and the semiconductor substrate 1 is formed through the hole H. Since the high-concentration impurity regions 1 η, I n ′ formed on both sides of the semiconductor substrate 1 are connected, the anode and the power source of the photodiode can be electrically guided to the same surface (front surface) of the semiconductor substrate 1. Although the strength of the substrate is reduced by thinning, a supporting substrate is provided on the back surface side of the semiconductor substrate 1, which can be reinforced during the pre-processing (process) step. For the first time, a photodiode array equipped with a photodiode will become commercially viable. Furthermore, since this photodiode array is of the back-illuminated type, it has a high signal-to-noise ratio and can be used for a highly accurate detection device.

In addition, the above-described method for manufacturing a back-illuminated photodiode array further includes a step of embedding a resin R in the hole H, and improving the strength of the semiconductor substrate 1 by embedding the resin in the hole H. Can be. The resin to be embedded in the hole H has photosensitivity. According to the above-described manufacturing method, a step of applying a photoresist to be the resin to the entire surface on the other surface (front surface) side of the semiconductor substrate 1 includes: The method further includes a step of removing only the photoresist in the region where the electrode (h2, OM) on the other surface side of the substrate 1 is to be formed, and a step of forming the electrode h2 in the region where the photoresist has been removed. In addition, the resin R can be buried by a normal photolithography process using a photoresist, and an electrode having a contact formed by an oxide film patterned with a photoresist can be exposed before the electrode is formed.

 The semiconductor substrate 1 and the high-concentration impurity regions 1 n and In ′ are of the first conductivity type (n-type in the above), and the plurality of photodiodes are a plurality of impurity types in the second conductivity type (p-type in the above). The anode or the force sword, which is composed of 1 p and the semiconductor substrate 1 and is located on one side (back side) of one of the photodiodes, is electrically guided to the other side (front side). "'In addition, the above-described manufacturing method includes a step of forming a first-conductivity-type (n-type in the above) full-surface impurity semiconductor layer 1nc shallower than the high-concentration impurity region over the entire surface on one side of the semiconductor substrate 1. Therefore, the entire impurity semiconductor layer 1nc can function as an accumulation layer.

Further, since the above-described manufacturing method includes a step of forming the oxide film 2 on one surface side (back surface) of the semiconductor substrate 1, it can function as a protective film. Further, from the viewpoint of three-dimensional mounting, the above-described method for manufacturing a back-illuminated photodiode array includes a bump B on the front side of the semiconductor substrate 1 so that the anode and the power source of the photodiode are electrically connected to the circuit board C. And a process of attaching to the circuit board C via the In this case, the connection node of the photodiode node and the force source electrically connected to the circuit board C by the bump B can extend in the circuit board direction, that is, the thickness direction of the semiconductor substrate 1, so that the mounting area is reduced. It can be smaller. - Also, in the above-described back-illuminated photodiode array, high-concentration impurity regions 1 n and In ′ are formed on the back side and the front side of the semiconductor substrate 1, and PN junctions are formed on the front side of the semiconductor substrate 1, respectively. In the back-illuminated photodiode array selectively connected to the anode and the force node of the photodiode thus formed, the high-concentration impurity regions 1 η and In ′ are connected to each other through a hole H penetrating the semiconductor substrate 1 in the thickness direction. It is electrically connected, and the resin H is filled in the hole H.

 The backside illuminated photodiode array has advantages in three-dimensional mounting and manufacturing method, and the resin in the holes can suppress a decrease in the substrate strength of the backside illuminated photodiode.

 In addition, according to the structure of the back-illuminated photodiode array, the semiconductor substrate 1 and the high-concentration impurity regions I n and I n ′ are of the first conductivity type (11 type in the above description). The photodiode formed on the other surface side is composed of the impurity region 1 p and the semiconductor substrate 1 of the second conductivity type (above!) Type. Since there is a shallow first-conductivity-type whole-surface impurity semiconductor layer 1 nc, the whole-surface impurity semiconductor layer 1 nc can function as an accumulation layer, and high-performance detection can be performed.

 Figure 2 shows the back-illuminated photodiode array shown in Figure 1J? FIG. 3 is an explanatory diagram of an imaging device including a plurality of 0s on a circuit board. According to the configuration described above, three-dimensional mounting is possible, so that a back-illuminated photodiode array PDA with a small dead space in a plurality of planar directions can be two-dimensionally arranged without gaps. That is, it is possible to provide an imaging device having a larger area as a whole.

Note that such large-area back-illuminated photodiode arrays are applied to X-ray computer tomography (CT) equipment, specifically, panel-shaped multi-X-ray CT equipment and positron emission tomography (PET) equipment. can do. In the case of such a device, a two-dimensionally divided scintillator (BGO, CS 等, CWO, etc.) is provided on the light incident surface. In the above-described polishing step, chemical polishing can be used in addition to mechanical polishing, and the exposed surface of the semiconductor substrate 1 can be mirror-finished. Further, the entire impurity semiconductor layer 1nc on the rear surface side functions as an accumulation layer. The accumulation layer can be at ground potential, but it can also be given a positive potential so that a reverse bias is applied.

 Further, in the above-mentioned back-illuminated photodiode array, the ultraviolet sensitivity can be improved because the entire impurity semiconductor layer serving as the accumulation layer can be formed thin.

 Also, in the process before the removal of the support substrate 3, after forming the electrodes OM and filling the common electrode extraction holes, a dicing tape is attached to the semiconductor substrate 1, and the dicing is performed. After performing a dicing blade to a position where 1 is separated as a chip (a position reaching the oxide film 4), the bonded support substrate 3 can be removed by mechanical polishing and dry etching. In this case, other methods such as laser can be adopted in addition to the normal blade dicing.

 In this manufacturing method, since all processes up to the end of dicing are performed on a thick wafer, the productivity of the process is high, and an epoch-making single-sided electrode photodiode production method capable of improving the yield is achieved. A bias can be applied via the bump B, and not only a photodiode with a simple zero bias, but also a high-speed, low-noise sensor (PIN photodiode, avalanche photodiode) can be realized. According to the backside illumination type photodiode array and the method of manufacturing the same of the present invention, mass production becomes possible.

Industrial applicability

 INDUSTRIAL APPLICABILITY The present invention can be used for a back-illuminated photodiode array and a method for manufacturing the same.

Claims

Area of claim  1. In a method of manufacturing a back-illuminated photodiode array,  (a) forming a high-concentration impurity region on one side of the semiconductor substrate according to a rule;  (b) a step of bonding a support substrate to the one surface side of the semiconductor substrate, and (c) a step of polishing the other surface side of the semiconductor substrate to make the semiconductor substrate thinner,  (d) forming a high-concentration impurity region and a plurality of photodiodes on the other surface side of the semiconductor substrate;  (e) forming a hole reaching the high concentration impurity region on the one surface side from the high concentration impurity region on the other surface side of the semiconductor substrate;  (f) electrically connecting the high-concentration impurity regions on the one surface side and the other surface side via the holes;  (g) removing the support substrate after the step (f); A method of manufacturing a backside illuminated photodiode array, comprising:  2. The semiconductor substrate and the high-concentration impurity region are of a first conductivity type, and the plurality of photodiodes include a plurality of second conductivity type impurity regions and a semiconductor substrate; 2. The method for manufacturing a back-illuminated photodiode array according to claim 1, wherein an anode or a force source located on one side is electrically led to the other side.  3. The backside irradiation according to claim 1, further comprising a step of forming a first-conductivity-type full-surface impurity semiconductor layer shallower than the high-concentration impurity region over the entire surface on one surface side of the semiconductor substrate. For manufacturing a photo diode array.  4. The method for manufacturing a back-illuminated photodiode array according to claim 1, further comprising a step of forming an oxide film on one side of the semiconductor substrate. 5. The method further comprising the step of embedding a resin in the hole. 2. The method for manufacturing a back-illuminated photodiode array according to item 1.  6. The resin to be embedded in the hole has photosensitivity, and a step of applying a photoresist as the resin to the entire surface on the other surface side of the semiconductor substrate; 2. The method for manufacturing a back-illuminated photodiode array according to claim 1, further comprising: a step of removing only a photoresist; and a step of forming an electrode in a region where the photoresist is removed. Method.  7. The method according to claim 1, further comprising: attaching the other surface of the semiconductor substrate to the circuit board via a bump so that the anode and the power source of the photodiode are electrically connected to the circuit board. 2. The method for producing a backside illuminated photodiode array according to claim 1.  8. High-concentration impurity regions are formed on one surface side and the other surface side of the semiconductor substrate, and the back surface is selectively connected to an anode and a cathode of a photodiode formed on the other surface side of the semiconductor substrate, respectively. In the irradiation type photodiode array, the high-concentration impurity regions are electrically connected to each other through a hole penetrating the semiconductor substrate in a thickness direction, and the hole is filled with a resin. Features backside illuminated photodiode array.  9. The semiconductor substrate and the high-concentration impurity region are of a first conductivity type, and a photodiode formed on the other surface side of the semiconductor substrate is composed of a second conductivity type impurity region and a semiconductor substrate; 9. The back-illuminated photodiode array according to claim 8, further comprising a first-conductivity-type full-surface impurity semiconductor layer shallower than the high-concentration impurity region on the entire surface on one side of the substrate.