JP2011096921A - Detector, sensor, and method of manufacturing the detector and the sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detector which is improved in economy and high in manufacturing yield, and does not generate a short circuit between adjacent pixels, and to provide a sensor, and a method of manufacturing the detector and the sensor. <P>SOLUTION: The detector includes: a light-receiving element array 50 where a plurality of light-receiving elements P are arranged in a compound semiconductor having a light reception sensitivity of a wavelength of 1 to 3 μm; a CMOS 70 for reading a photocharge for each pixel; a junction bump 9 interposed between the light-receiving element array and the CMOS; and a cylindrical metal G, namely a barrel, subjected to conductive connection to the junction bump 9. The cylindrical metal G is provided at either the side of the light-receiving element array or the side of the CMOS and positioned to house the junction bump 9. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a detection device, a sensor having a light receiving sensitivity from the near infrared region to the infrared region, and a manufacturing method thereof.

In a detection device having a photodiode array formed on a compound semiconductor, a readout electrode of a signal readout silicon IC (ROIC: Read Out IC) and the electrode of the photodiode are opposed to each other by a bump interposed between the two. Conduction is taken. Since a photodiode is formed of a compound semiconductor in the near infrared region or infrared region longer than the visible region, it may be called a hybrid configuration of a compound semiconductor and silicon (IC). Since the above compound semiconductor crystals are weak against mechanical force, soft indium (In) having a low melting point is often used for the bumps.
Due to the above characteristics, the indium bumps tend to be irregular and irregular when provided on the photodiode electrode or the ROIC readout electrode. One detection device is provided with tens of thousands to hundreds of thousands of bumps, but it is difficult to prevent such bumps having a large shape deviation. A bump having a large shape deviation does not realize one-to-one conduction during crimping, brazing, or the like, and protrudes from the bump area (the pixel area) to contact an adjacent bump to cause a short circuit. Such a short circuit is unsightly in the case of imaging, and causes a reduction in resolution in the case of substance detection and inspection, thus reducing the commercial value.

  Many proposals have been made to solve the above problems. In order to uniformly control the shape of the In bump in the hybrid configuration, (d1) the electrode itself connected to the In bump or the surface layer of the electrode is made of a metal that forms a eutectic with indium at a temperature lower than the melting point of indium. A method has been proposed in which the connection is made with little pressure applied when connecting to the In bumps (Patent Document 1). In addition, (d2) a proposal has been made that multi-step processing is performed on an epitaxial wafer to form a concave pad so that indium protrudes laterally during In bump bonding and no short circuit occurs between adjacent pixels (Patent Document 2). In addition, (d3) a proposal was made to put the In bump after bonding into a shape that does not cause a short circuit between adjacent pixels by inserting a gap adjusting member and controlling the bonding process (Patent Document 3). Furthermore, (d4) a method of using an insulating resin (polyimide) grid-like member, putting an In bump into a hole in the grid, surrounding the In bump by a non-hole, and isolating it from an adjacent In bump ( Patent Document 4).

JP-A-9-82757 JP-A-2-174261 JP 2002-299650 A JP-A-7-153905

The improved methods (d1) to (d4) have the following problems.
I. Common problems (d1) to (d4) above all use MCT (HgCdTe) for the light receiving part and use at -40 ° C to liquid nitrogen temperature (-196 ° C), thereby suppressing noise current. A clear image is obtained. On the contrary, if it is not cooled, a clear image cannot be obtained, and high resolution cannot be obtained in the detection of substances and the like. However, due to the thermal stress accompanying cooling, damage to the sensor (compound semiconductor), short circuit between adjacent pixels, detachment of the joint, and the like are likely to occur. In order to prevent these troubles, soft In bumps that are easily deformed and do not propagate stress are used for the bonding bumps of the hybrid structure as described above. However, since indium has a low melting point of 150 ° C. to 160 ° C., it is difficult to ensure reliability in a high temperature environment.
II. Problems in each improved method (d1): (i) If the In bump shape is uniformly aligned at all joints and the distance between the (photodiode sensor / IC) cannot be reliably controlled at the time of joining, melting will occur. The indium which protrudes causes a short circuit between adjacent pixels. (Ii) Even if a short circuit does not occur at the time of bonding, deformation occurs due to a thermal cycle (cooling when MCT is used / heating to normal temperature when not using), and the distance between In bumps between adjacent pixels is short. A short circuit occurs when touched. Due to the above (i) and (ii), the effect is small for the increase in man-hours.
(D2): High-precision machining is required to perform multistage machining, control is difficult, and man-hours increase. For this reason, a yield falls and it causes a manufacturing cost increase.
(D3) and (d4): An interval adjusting member or a lattice-like member is required, and process control at the time of joining using the member is difficult. That is, the manufacturing cost is increased and it is difficult to ensure reliability.

  An object of the present invention is to provide a detection device, a sensor, and a method of manufacturing the same, which are excellent in economic efficiency and enable a high manufacturing yield and do not cause a short circuit between adjacent pixels.

  The detection apparatus according to the present invention includes a light receiving element array in which a plurality of light receiving elements made of a compound semiconductor having light receiving sensitivity in the near infrared region are arranged, a readout circuit that reads out photoelectric charges for each pixel, and a light receiving element array and a readout circuit. And a cylindrical conductive member that is a cylindrical body that is conductively connected to the bonding bump. The cylindrical conductive member is provided on either the light receiving element array side or the readout circuit side. The bonding bump is provided on the other side where the cylindrical conductive member is not provided, and the cylindrical conductive member is positioned so as to accommodate the bonding bump.

According to the above configuration, when the light receiving element array and the readout circuit are coupled with the bonding bump interposed, the coupling bump is inserted into the cylindrical conductive member facing the bonding bump so as to accommodate the bonding bump. Can be realized. In the light receiving element array, a very large number of pixels are arranged at a short pitch, and therefore a very large number of bonding bumps are also arranged at a short pitch. Some of the many bonding bumps deviate from a normal shape. The cylindrical conductive member according to the present invention can accommodate the bonding bump even if the bonding bump slightly deviates from the normal shape, and can prevent the adjacent pixel from protruding greatly. In other words, the cylindrical conductive member can also hold a bonding bump whose shape has deviated, and the bonding bump does not protrude greatly next to the cylindrical conductive member. As a result, the rate at which adjacent pixels are short-circuited can be greatly reduced. The near-infrared region refers to a short wavelength region in the infrared region, for example, a range that exceeds the wavelength of the visible light region and is about 3 μm. Since living organisms, organic substances, and the like have many absorption bands in the near infrared region, they can exert great power in various detections including living organisms and organic substances.
Here, the terms “one”, “both”, “other”, “other”, and the like are used to refer to the light receiving element array and the readout circuit, but it can be determined by common sense from the context before and after. In addition, providing a bump or a cylindrical conductive member on one or the other side before coupling the light receiving element array and the readout circuit with a bump interposed therebetween is expressed by “providing” or “forming”. The terms “bonding”, “connection” and “crimping” because a load is used are used as the terms indicating the above-mentioned connection.
For the cylindrical conductive member, the inner diameter surface, the inner side surface, and the inner wall surface are used in the same meaning, and for the bonding bump, the outer peripheral surface and the outer surface are used in the same meaning. For a cylindrical conductive member or bonding bump, the “tip” or “tip” refers to the tip in the direction toward the other side, and conversely, the “root” refers to the light receiving element array or readout circuit in which it is provided. A close part.

  The inner diameter of the cylindrical conductive member can be made larger than the outer diameter of the bonding bump. As a result, even if the cylindrical conductive member has a large degree of deviation in the shape of the bonding bump, it is possible to easily accommodate the bonding bump and prevent protrusion.

  The height of the cylindrical conductive member can be made larger than the height of the bonding bump. Thereby, the cylindrical conductive member can easily accommodate the bonding bump, and can more reliably prevent the protrusion. For example, if the light receiving element array is not exactly flat and the central part is slightly raised, the bonding bumps are housed deep in the central part of the light receiving element array, but the dead end is not reached, and the height of the bonding bumps Holds up to one cup. For this reason, even at the edge portion of the light-receiving element array, the bonding bumps have a small accommodation depth, but are accommodated in the cylindrical conductive member, making it easy to obtain an effective conductive connection.

  It is preferable that the cylindrical conductive member has an inner diameter that increases from the root toward the tip. Accordingly, the cylindrical conductive member can easily accommodate or hold the bonding bump, and can easily prevent a short circuit with an adjacent pixel. Further, when the joining bump enters the inner diameter of the cylindrical conductive member, it can easily conduct electricity by rubbing against the inner diameter surface, and the contact resistance can be reduced. As a result, it is possible to obtain a detection device with few electrical open defects (non-contact defects) and few defective pixels due to short circuits or the like.

  The outer diameter of the bonding bump can be made smaller than the inner diameter at the tip of the cylindrical conductive member at the bump tip and larger than the inner diameter at the tip of the cylindrical conductive member at the bump root. As a result, it is possible to obtain a detection device with fewer electrical open defects (non-contact defects) and fewer defective pixels due to short circuits or the like, more reliably regardless of the contact state of the front end of the pump.

A bottom conductive part for closing the bottom of the cylindrical conductive member can be provided. According to this, in addition to the conductive connection form by rubbing the outer surface of the bonding bump and the inner surface of the cylindrical conductive member, the bonding bump is made thin and long and inserted into the cylinder of the cylindrical conductive member with a margin. Then, the conductive connection can be established by abutting the tip portion against the bottom conductive portion. For this reason, for example, when the center of the surface of the light receiving element array is slightly convex toward the readout circuit side, the cylindrical conductive member or the bonding bump protrudes from the slightly inclined surface. Even in such a case, the combination of the narrow and long bonding bump and the cylindrical conductive member having the bottom conductive portion allows the bonding bump to be accommodated in the cylindrical conductive member so that no protruding portion is generated.
Even if the bottom conductive part is not provided (only the cylindrical body of the cylindrical conductive member), the protective film is disposed on the bottom of the cylinder, so that when the height of the bonding bump is large, it is bonded to the bottom protective film. The tip of the bump hits and is deformed, and a conductive connection can be established with the inner diameter surface of the cylindrical conductive member. Further, even in the case of the cylindrical conductive member having the bottom conductive portion as described above, the outer side surface of the bonding bump and the inner side surface of the cylindrical conductive member can be rubbed and conductively connected.

  The tip of the cylindrical conductive member can be tapered so as to reduce the inner diameter from the tip to the inner peripheral surface while leaving the end on the outer peripheral surface side thin and reducing the thickness. As a result, even if the bonding bump is somewhat deformed, it can be reliably accommodated in the cylindrical conductive member.

  The cylindrical conductive member can be a pixel electrode fixed to the light receiving element array. Thus, for example, in an InP-based light receiving element array, a cylindrical conductive member can be used as the p-side electrode. For this reason, the cylindrical conductive member also serves as the p-side electrode, so that a short circuit with the adjacent electrode can be prevented, and the manufacturing cost can be reduced while obtaining a high-quality image or high resolution detection capability.

The cylindrical conductive member can be a metal containing Zn and / or Pt. Accordingly, the cylindrical conductor can easily realize the conductive connection with the bonding bump while being in ohmic contact with the p ⁺ type InP region in the InP-based light receiving element array, for example.

  The bonding bump can include In and / or Sn. (1) The bonding bump containing In as a main component is soft and can be electrically connected even at a normal temperature without being heated to a very high temperature. A light-receiving element array mainly composed of compound semiconductors is easily damaged by local pressure as described above. However, due to the characteristics of In, mechanical damage to the light-receiving element array and peeling of the joint due to thermal stress occur. No cooling type detection device can be configured. (2) According to bonding bumps (SnAu, SnAg, etc.) containing Sn as a main component, high-strength bonding can be easily obtained, and reliability in a high-temperature environment can be increased.

The light receiving element array has an InP substrate and a light receiving layer having a band gap wavelength of 1.65 μm to 3.0 μm provided on the InP substrate, and the light receiving layer is made of InGaAsNP, InGaAsNSb, and InGaAsN. It can be set as the structure which is either. This makes it possible to obtain a sensor or detection device having sensitivity even in the long wavelength region of the near infrared region with little or no cooling. Note that the above InGaAsNP, InGaAsNSb, and InGaAsN are all epitaxially grown layers that lattice match with InP. The lattice matching condition means that | Δa / a | ≦ 0.002 is satisfied, where a is the lattice constant of the InP substrate and Δa is the difference from the lattice constant of the target epitaxial growth layer.
According to the above configuration, the light receiving element array in the near-infrared region has low noise and can be used at -40 ° C. to + 80 ° C., depending on the crystallinity of the light receiving element array. If it can be reliably joined at the time of manufacture, it is possible to eliminate degradation of resolution and image quality such as generation of stress due to cooling → deformation → peeling of the joint.

The light receiving element array has an InP substrate and a light receiving layer having a band gap wavelength of 1.65 μm to 3.0 μm provided on the InP substrate, and the light receiving layer includes GaAsSb / InGaAs, GaAsSb / InGaAsN, and GaAsSb. The structure may be a type II type quantum well structure made of / InGaAsNP or GaAsSb / InGaAsNSb. Also in this case, the above quantum well structures are all epitaxially grown layers lattice-matched with InP, and the lattice matching conditions are the same as described above.
With the above structure, a material having a melting point higher than that of In can be used for the bonding bump, and a highly reliable near-infrared detection device with less deterioration of the bonding portion even under a high temperature environment can be realized. Examples of the material having a higher melting point than In include Sn ₉₀ Au ₁₀ (melting point around 220 ° C.), Sn _96.5 Ag _3.5 (around 220 ° C.), and the like. In addition, Sn-based materials are superior in wettability to metals compared to In-based materials, and therefore bonding can be performed without imposing strict control conditions. In addition, it is possible to obtain a near-infrared detector having a high reliability at high temperatures, a small number of defective pixels, and excellent resolution.

  The sensor of the present invention is constituted by a light receiving element array used in any one of the detection devices described above. Accordingly, even when a detection device having a hybrid structure is manufactured, a high-quality image or high resolution can be easily obtained without causing a short circuit.

The sensor manufacturing method of the present invention is a method of manufacturing a sensor of a light receiving element array in which a plurality of light receiving elements are arranged on a compound semiconductor having light receiving sensitivity in the near infrared region. This manufacturing method includes a step of forming a cylindrical electrode for each light receiving element so as to be in ohmic contact with the light receiving element on the surface of the epitaxial layer of the compound semiconductor.
By manufacturing the sensor by the above manufacturing method, even if the pixel electrode and the readout electrode are conductively connected using the bonding bumps to produce a hybrid structure detection device, a high-quality image without causing a short circuit, or High resolution can be easily obtained.

  In the step of forming the cylindrical electrode, the cylindrical conductive member can be formed by vapor deposition using a photolithography method, or can be formed using a plating method after vapor deposition using a photolithography method. This makes it possible to easily obtain a highly accurate cylindrical electrode using a technique with a lot of technical accumulation.

The method for manufacturing a detection device according to the present invention includes a step of preparing a light receiving element array in which a plurality of light receiving elements are arranged on a compound semiconductor having light receiving sensitivity in the near infrared region, and a read circuit for reading out photocharge for each light receiving element. In the step of preparing and the step of preparing the light receiving element array and the readout circuit, a cylindrical conductive member is formed for each electrode on either the electrode of the light receiving element or the electrode of the readout circuit. A bonding bump is formed on the other side where the cylindrical conductive member is not formed, and the light receiving element array and the readout circuit are faced and aligned, and (1) the bonding bump is formed on the cylindrical body. While applying pressure so as to be accommodated, or (2) raising the temperature above the melting point of the junction bump while the junction bump is accommodated in the cylindrical body, or (3) the junction bump being in the cylinder And a step of joining by raising the temperature above the melting point of the joining bump while applying pressure so as to be accommodated in the body.
According to the above manufacturing method, it is possible to easily obtain a high-quality image without a short circuit or a detection device exhibiting high resolution by the cylindrical conductive member and the bonding bumps accommodated in the cylindrical conductive member. .
The step of joining by applying the pressure (1) may be performed in a heating atmosphere or in the atmosphere at room temperature.
Since pressure is required to bring the bonding bumps into contact with the cylindrical metal, do not apply pressure when melting the bumps after applying moderate pressure, or control the distance between the two. Often desirable. The above (2) is intended for such a joining method. The above (3) is intended for a bonding method in which an appropriate pressure is maintained in (2).

  According to the present invention, it is possible to obtain a detection apparatus or the like that is excellent in economic efficiency and that does not cause a short circuit between adjacent pixels while enabling a high manufacturing yield.

It is sectional drawing which shows the detection apparatus in Embodiment 1 of this invention. It is a figure which shows the cylindrical metal and joining bump which are shown in FIG. It is the top view which looked at the light receiving element array of the detection apparatus of FIG. 1 from the multiplexer side. FIG. 4 is an enlarged view of a pixel in FIG. 3. It is a figure for demonstrating the light receiving element array in the detection apparatus of this Embodiment. 1A and 1B show a connection portion of a pixel readout portion in the hybrid structure shown in FIG. 1, in which FIG. 1A shows a normal arrangement, and FIG. 1B shows a case where a deviation occurs from a normal position. It is a figure which shows the conditions which side surfaces rub in this Embodiment. It is sectional drawing which shows the detection apparatus in Embodiment 2 of this invention. The connection aspect of the joining bump and cylindrical metal G in this Embodiment is shown, (a) is the state which the joining bump contacted the pad by the side of a cylindrical metal, (b) is pushed in, and the tip of a joining bump bulges out It is a figure which shows the state made to do. It is a figure which shows a pixel connection part when the light receiving element array becomes a curved surface. It is a detection apparatus in the modification of Embodiment 2, and is sectional drawing which shows the embodiment of this invention. It is sectional drawing which shows the detection apparatus in Embodiment 3 of this invention.

(Embodiment 1)
FIG. 1 is a cross-sectional view showing a detection device 100 according to Embodiment 1 of the present invention. The light-receiving element array 50 is formed in a laminate of n-type InP substrate 1 / n-type buffer layer 2 / light-receiving layer (light absorption layer) 3 / InP cap layer 4. In each light receiving element, the p-type impurity zinc (Zn) is selectively diffused and introduced, the p-type region 6 is formed, and the pn junction 15 is formed. The p-type region 6 is in ohmic contact with a cylindrical metal G that is a cylindrical conductive member that also serves as an electrode of the pixel P. The cylindrical metal G of the p-side electrode is held so as to accommodate the bonding bump 9, and the cylindrical metal G and the bonding bump 9 are conductively connected, and the reading circuit (multiplexer) 70 reads through the bonding bump 9. It is connected to the electrode 71. The light receiving element composed of the p-type region 6 / the region including the cylindrical metal G is a portion corresponding to the pixel P, and thus the cylindrical metal G is a pixel electrode. The n-side electrode 12 that applies a common ground potential to the pixel electrodes G is in ohmic contact with the back surface of the n-type InP substrate 1 and connected to an external ground. An antireflection film 35 made of a SiON film is disposed on the back surface of the InP substrate 1 serving as an incident surface on which light is incident. The SiN selective diffusion mask pattern 36 used for selective diffusion for forming the p-type region 6 is left as it is, and the opening of the selective diffusion mask pattern 36 or the surface of the InP cap layer 4 and the selective diffusion mask. A protective film 43 covering the pattern 36 is provided.

  In FIG. 1, the light receiving layer 3 may be any light receiving layer as long as it has light receiving sensitivity at a wavelength of 1 μm to 3 μm. For example, it can be any one of InGaAsNP, InGaAsNSb, and InGaAsN. In particular, when the light-receiving layer 3 has a type II multiple quantum well structure, when diffusing p-type impurity zinc (Zn), in order to suppress the Zn concentration in the multiple quantum well structure below a predetermined level, A diffusion concentration distribution adjusting layer is provided on the InP cap layer 4 side. In FIG. 1, when the light receiving layer 3 has a multiple quantum well structure, it can be considered that a diffusion concentration distribution adjusting layer is included in the InP cap layer 4. A specific structure in the case where the light receiving layer 3 has a multiple quantum well structure will be described in detail later.

  A CMOS (Complementary Metal Oxide Semiconductor) is used for the multiplexer of the readout circuit 70. One readout electrode 71 or pad 71 is provided for each cylindrical metal G that is a pixel electrode, and the bonding bump 9 is disposed on the pad 71. Before being connected to the detection device 100 having a hybrid structure, the bonding bump 9 is provided for each pad 71 in the CMOS 70 of the readout circuit. At the time of connection or pressure bonding, the bonding bump 9 is accommodated and conductively connected so as to be held by the cylindrical metal G provided in the light receiving element array 50 or the sensor 50. One ground electrode 72 is provided in the CMOS in common with each readout electrode 71 of the readout circuit 70.

  FIG. 2 is a diagram showing the shapes of the cylindrical metal G and the bonding bumps 9 before pressure bonding. The cylindrical metal G is tapered such that the inner diameter increases toward the tip end t, and the root portion b is in ohmic contact with the p-type region 6. The bonding bump 9 has an outer diameter that decreases toward the tip end portion 9 a, and the root portion 9 b is connected to the CMOS pad 71. Even if the bonding bump 9 deviates somewhat from the normal shape at the initial stage of crimping (the stage where the mutual tips start to touch), the tip 9a of the bonding bump 9 is moved by the wide mouth of the tip t of the cylindrical metal G. Easy to accommodate. If the tip end portion 9a of the bonding bump 9 is accommodated in the mouth of the tip end portion t of the cylindrical metal G, the bonding bump 9 is pushed into the cylindrical metal G without protruding from the post-compression stage. For this reason, it is possible to prevent a short circuit due to contact with the bonding bump 9 of the adjacent pixel.

FIG. 3 is a view of the light receiving element array 50 as viewed from the side of the multiplexer 70. For example, the number of pixels P is 320 × 256 (approximately 82,000 pixels), and the pitch is 30 μm.
FIG. 4 is a diagram illustrating the pixel P. A broken-line circle indicates a p-type region 6 in which a cylindrical metal G having a tip portion t and a root portion b is located. The InP cap layer 4 constituting the surface layer of the p-type region 6 is covered with a protective film 43 such as SiON. Although the light receiving element and the pixel P do not exactly match each other in terms of a planar area, the pixel P and the light receiving element have a one-to-one correspondence. Therefore, in this description, the light receiving element and the pixel P are arranged in the same column. deal with.

FIG. 5 is a diagram in the case where the light receiving layer 3 in the light receiving element array 50 has a type II multiple quantum well structure in the present embodiment. In FIG. 5, the light receiving element P of each pixel has a III-V group semiconductor laminated structure (epitaxial wafer) having the following configuration on the InP substrate 1.
(InP substrate 1 / n-type In _0.53 Ga _0.47 As buffer layer 2 / type II InGaAs and GaAsSb light-receiving layer 3 / diffusion concentration distribution adjusting layer 14 / InP cap layer 4)
In the p-type region 6 positioned so as to reach the light-receiving layer 3 having the multiple quantum well structure from the InP cap layer 4, Zn of the p-type impurity is selectively diffused from the opening of the selective diffusion mask pattern 36 of the SiN film. Formed with. Introducing diffusion within the periphery of each pixel in a plane-limited manner is realized by diffusing using the selective diffusion mask pattern 36 of the SiN film.
The cylindrical metal G is in ohmic contact with the p-type region 6. The metal of the cylindrical metal G is preferably made of Au / Zn / Au / Ti / Au in order to make ohmic contact and have a predetermined level of strength. Further, an n-side electrode 12 of AuGeNi / Ti / Au is provided on the n-type InP substrate 1 so as to make ohmic contact.

In the light-receiving layer 3 having the multiple quantum well structure, a pn junction 15 is formed at a position corresponding to the boundary front of the p-type region 6, and a reverse bias voltage is applied between the p-side electrode G and the n-side electrode 12. As a result, a depletion layer is formed more widely on the side where the n-type impurity concentration is low (n-type impurity background). The background in the light-receiving layer 3 having the multiple quantum well structure is about 5 × 10 ¹⁵ / cm ³ or less in terms of n-type impurity concentration (carrier concentration). The position 15 of the pn junction is determined by the intersection of the background (n-type carrier concentration) of the light-receiving layer 3 of the multiple quantum well and the concentration profile of the p-type impurity Zn. In order to improve the electrical conductivity with the p-side electrode G while the light-receiving layer 3 having the multiple quantum well structure is made not to lose the crystallinity by selectively introducing p-type impurities, A diffusion concentration distribution adjusting layer 14 is inserted between the cap layer 4 and the cap layer 4. The Zn concentration is increased in the thickness portion on the cap layer 4 side in the diffusion concentration distribution adjustment layer 14 and the Zn concentration is decreased in the thickness portion on the light receiving layer 3 side as described above. In the diffusion concentration distribution adjusting layer 14, the concentration of the p-type impurity selectively diffused from the surface of the InP cap layer 4 is steep from the high concentration of 1 × 10 ¹⁸ / cm ³ or more on the InP cap layer side to the light receiving layer side. Make it fall. The diffusion concentration distribution adjusting layer 14 is preferably formed of InGaAs, which has a relatively low bandgap energy, so that the electrical resistance is unlikely to increase even when there is a thickness portion where the impurity concentration is low (a predetermined thickness portion on the light receiving layer side). In FIG. 1, the diffusion concentration distribution adjusting layer is not shown, but in order to improve the crystallinity of the light receiving layer 3 having the multiple quantum well structure, the diffusion concentration distribution adjusting layer 14 should be provided. However, the diffusion concentration distribution adjusting layer may not be provided.
By inserting the diffusion concentration distribution adjusting layer 14 as described above, an impurity concentration of 5 × 10 ¹⁶ / cm ³ or less can be easily and stably realized in the light receiving layer 3. The light receiving element array 50 targeted by the present invention seeks to have light receiving sensitivity from the near-infrared region to the longer wavelength side, so that the cap layer 4 has a band gap energy larger than the band gap energy of the light receiving layer 3. It is preferable to use materials. For this reason, InP, which is a material having a larger band gap energy and better lattice matching than the light receiving layer, is usually used for the cap layer 4. InAlAs having substantially the same band gap energy as InP may be used.

  The light receiving layer 3 is preferably a type II multiple quantum well structure. In the type I quantum well structure, in the case of a light receiving element that has a light receiving sensitivity in the near infrared region while sandwiching a semiconductor layer having a small band gap energy between semiconductor layers having a large band gap energy, a semiconductor layer having a small band gap energy is used. The upper limit wavelength (cutoff wavelength) of the light receiving sensitivity is determined by the band gap. That is, transition of electrons or holes due to light is performed in a semiconductor layer having a small band gap energy (direct transition). In this case, the material for extending the cutoff wavelength to a longer wavelength region is very limited in the III-V compound semiconductor. On the other hand, in the type II quantum well structure, when two different semiconductor layers having the same Fermi energy are alternately stacked, the conduction band of the first semiconductor and the valence band of the second semiconductor are obtained. The upper limit of the wavelength (cutoff wavelength) of the light receiving sensitivity is determined. That is, transition of electrons or holes by light is performed between the valence band of the second semiconductor and the conduction band of the first semiconductor (indirect transition). For this reason, the energy of the valence band of the second semiconductor is made higher than that of the first semiconductor, and the energy of the conduction band of the first semiconductor is made lower than the energy of the conduction band of the second semiconductor. By doing so, it is easier to realize a longer wavelength of light receiving sensitivity than in the case of direct transition in one semiconductor.

As described above, the selective diffusion using the selective diffusion mask pattern 36 allows the p-type impurity to be diffused and introduced into the periphery from the periphery of the light receiving element in a planar manner. It is not exposed on the end face of As a result, leakage of photocurrent is suppressed. As shown in FIG. 5, a plurality of pixels P are arranged without element isolation grooves. As described above, the p-type region 6 is limited to the inner side of the pixel P and is reliably separated from the adjacent pixel P.
On the InP substrate 1, an n-type InGaAs buffer layer 2 (or n-type InP buffer layer 2) having a thickness of 2 μm is formed. Next, the light receiving layer 3 having a multiple quantum well structure of (InGaAs / GaAsSb) or (InGaAsN / GaAsSb) is formed. The composition of InGaAs is In _0.53 Ga _0.47 As and the composition of GaAsSb is GaAs _0.52 Sb _0.48 so as to lattice match with InP. As a result, the degree of lattice matching (| Δa / a |: where a is a lattice constant and Δa is a lattice constant difference between them) can be 0.002 or less.
The InGaAs layer forming the unit quantum well structure has a thickness of 5 nm, the GaAsSb layer has a thickness of 5 nm, and the number of pairs (the number of repetitions of the unit quantum well) is 250. Next, an InGaAs layer having a thickness of 1 μm is epitaxially grown on the light receiving layer 3 as a diffusion concentration distribution adjusting layer 14 at the time of introducing Zn diffusion, and finally, an InP cap layer 4 having a thickness of 1 μm is epitaxially grown. Both the light receiving layer 3 and the diffusion concentration distribution adjusting layer 14 are preferably epitaxially grown by MBE (Molecular Beam Epitaxy) method. The InP cap layer 4 may be epitaxially grown by the MBE method, or after the diffusion concentration adjusting layer 14 is grown, the InP cap layer 4 may be removed from the MBE apparatus and epitaxially grown by the MOVPE (Metal Organic Vapor Phase Epitaxy) method. .

Since the InP substrate 1 is in ohmic contact with the n-side electrode 12 on the back surface, it is preferable to use a substrate containing an n-type impurity such as Si at a predetermined level or more. For example, it is preferable to contain about 1 × 10 ¹⁷ / cm ³ or more of an n-type dopant such as Si.
The InGaAs / GaAsSb multiple quantum well structure light-receiving layer 3, InGaAs diffusion concentration distribution adjusting layer 14, and InP cap layer 4 are preferably non-doped, but a very small amount of n-type dopant such as Si (for example, 2 × 10 ¹⁵ / cm 2). ^{About 3} ) Doping may be performed.
In FIG. 5, the pn junction 15 should be broadly interpreted as follows. In the light receiving layer 3, an impurity region (referred to as an i region) having a low impurity concentration in a region on the side opposite to the side where the p-type impurity element Zn is introduced by selective diffusion is regarded as an intrinsic semiconductor. This also includes a junction formed between the introduced p-type region 6 and the i region. That is, the pn junction may be a pi junction or the like, and further includes a case where the p concentration in the pi junction is very low.

As described above, by using the SiN selective diffusion mask pattern 36 formed on the surface of the InP cap layer 4, Zn is selectively diffused from the opening to receive the light-receiving layer having an InGaAs / GaAsSb (or InGaAsN / GaAsSb) multiple quantum well structure. The p-type region 6 is formed so as to reach within 3. The front tip of the p-type region 6 forms a pn junction 15. At this time, a high concentration region having a Zn concentration of about 1 × 10 ¹⁸ / cm ³ or more is preferably limited to the InGaAs diffusion concentration distribution adjusting layer 14. That is, the high-concentration impurity distribution continues from the surface of the InP cap layer 4 in the depth direction to the InGaAs diffusion concentration distribution adjustment layer 14 and further 5 × 10 5 at a deeper position in the diffusion concentration distribution adjustment layer 14. It decreases to ¹⁶ / cm ³ or less. The Zn concentration distribution in the vicinity of the pn junction 15 is a distribution indicating an inclined junction.

  According to the manufacturing method described above, the light receiving element array 50 is obtained by selective diffusion of Zn (diffusion whose periphery is limited in a plane so as to be inside the peripheral portion of the light receiving element) without performing mesa etching for element isolation. Adjacent light receiving elements are separated. That is, the Zn selective diffusion region 6 becomes a main part of one pixel portion P, but a region where Zn is not diffused separates each pixel. For this reason, it is possible to suppress dark current without being damaged by crystals accompanying the mesa etching.

  When the pn junction 15 is formed by selective diffusion of impurities, the diffusion proceeds not only in the depth direction but also in the lateral direction (direction perpendicular to the depth), so there is a concern that the element spacing cannot be reduced beyond a certain level. When the selective diffusion of Zn is actually performed, in the structure in which the InP cap layer 4 is provided on the outermost surface and the InGaAs diffusion concentration distribution adjusting layer 14 is disposed below, the lateral diffusion is performed in the depth direction. It was confirmed to be within the same level or lower. That is, in the selective diffusion of Zn, Zn spreads in the lateral direction with respect to the opening diameter of the selective diffusion mask pattern 36, but the extent is small, and as shown schematically in FIG. It only spreads a little more.

The selective diffusion mask pattern 36 and the InP cap layer 4 are covered with a protective film 43 made of polyimide resin or the like. Next, a cylindrical metal G that is a cylindrical conductive member that is in ohmic contact with the p-type region 6 through the protective film 43 is formed by a photolithography method or the like. The cylindrical metal G protrudes greatly from the protective film 43. It is preferable to use Au / Zn / Au / Ti / Au or the like so as to be in ohmic contact with the p-type region 6 using a sputtering method, a laser ablation method, or the like as the film forming method. At the time of forming the metal film, the cylindrical metal G is formed by the multilayer body described above, but is alloyed through a thermal history such as heat treatment. From the viewpoint of ensuring the above ohmic contact and strength, it is preferable to use a metal containing Zn and / or Pt. After forming a predetermined initial shape, the metal thickness may be increased by using a plating method together. Examples of the shape of the cylindrical metal G include the following.
Root part b: outer diameter φ20 μm, inner diameter φ10 μm
Tip t: outer diameter φ17 μm, inner diameter φ13 μm

  The InP substrate 1 is preferably an off-angle substrate inclined from 5 to 20 degrees in the [111] direction or the [11-1] direction from (100). More preferably, it is inclined from 10 to 15 degrees from (100) to the [111] direction or the [11-1] direction. By using such a large off-angle substrate, the InGaAs buffer layer 2, the type II multiple quantum well structure light receiving layer 3, the InGaAs diffusion concentration distribution adjusting layer 14, and the InP cap layer 4 having a small defect density and excellent crystallinity. Can be obtained.

The formation of the bonding bump 9 on the pad 71 of the CMOS 70 is also preferably performed using a photolithography method. The bonding bumps 9 may also be formed only by the vapor phase growth method, or the vapor phase growth method and the plating method may be used in combination. Examples of the material of the bonding bump 9 include In. In is soft and suitable for preventing mechanical damage to the III-V group compound semiconductor of the light receiving element array 50, peeling of the joint due to thermal stress, and the like. In addition, an alloy containing Sn such as SnAg and SnAu can easily obtain a high-strength bond and can improve reliability in a high-temperature environment.
Examples of the shape of the bonding bump 9 include the following. Although it is a target shape and a straight cylinder is the target shape, it may be slightly deviated as described above.
Outside diameter φ12μm
10 μm height
The shape of the bonding bump 9 and the cylindrical metal G is merely an example, and an appropriate shape that is unlikely to cause a short circuit with an adjacent pixel can be employed depending on how the light receiving element array 50 is deformed. .
Connection between the light receiving element array 50 and the CMOS 70 is performed by applying pressure to the light receiving element array 50 and the CMOS 70 in an appropriate temperature equal to or higher than the melting point of the bonding bump 9 and in a nitrogen atmosphere or in a normal temperature atmosphere.
In addition, the connection may be made by controlling the distance between the light receiving element array 50 and the CMOS 70 so that the bonding bump 9 and the cylindrical metal G are in contact with each other, instead of the method of connecting by controlling the pressure. That is, since pressure is required to bring the bonding bump 9 and the cylindrical metal G into contact with each other, an appropriate pressure is first applied, but no pressure is applied when the bonding bump 9 is melted after the application. In many cases, distance control between the two is desirable.

  FIGS. 6A and 6B are diagrams showing examples of conductive connection between the cylindrical metal G and the bonding bump 9. At the tip end t of the cylindrical metal G, a taper is provided to make the inner diameter gradually smaller toward the inner peripheral surface while reducing the thickness, leaving the end on the outer peripheral surface side thin. As a result, even if the bonding bump 9 is slightly deformed, it can be reliably accommodated in the cylindrical metal G. In FIG. 6A, the tip 9a of the bonding bump 9 enters the cylindrical metal G with a comparative margin, and is connected to the tip of the cylindrical metal G at a portion close to the root 9b of the bonding bump 9. In FIG. 6B, the planar position is shifted, and the bonding bump 9 is connected only on one side of the cylindrical metal G. In the present embodiment, since only the cylindrical metal G is exposed as an electrode on the p side, when conducting connection with the bonding bump 9, the inner side surface (inner wall surface) of the cylindrical metal G and the bonding bump 9 It is preferable to take a form in which the outer side surface of each other is rubbed. Therefore, it is preferable that the outer surface of the bonding bump 9 and the cylindrical metal G have a large taper in the above direction. By giving a large inclination, it is possible to increase the possibility that the side surfaces of the cylindrical metal G and the bonding bump 9 rub against each other while the bonding bump 9 is placed in the opening of the cylindrical metal G.

The condition shown in FIG. 7 can be derived from the connection form example shown in FIG. The opening or inner diameter Sa at the tip t of the cylindrical metal G is preferably larger than the outer diameter of the tip 9 a of the bonding bump 9. As a result, the tip end portion 9 a of the bonding bump 9 is easily accommodated in the cylindrical metal G. The outer diameter Rm at the middle of the bonding bump 9 or the outer diameter Rb at the base is preferably larger than the inner diameter Sc on the tip side of the cylindrical metal G. As a result, the outer surface of the bonding bump 9 rubs against the inner surface of the cylindrical metal G. The height h from the surface of the protective film 43 to the tip of the cylindrical metal G is preferably larger than the height d of the bonding bump 9. The outer surface of the bonding bump 9 can rub against the inner surface of the cylindrical metal G before the tip of the bonding bump 9 hits the protective film 43.
By rubbing the outer surface of the bonding bump 9 and the inner surface of the cylindrical metal G, it is possible to obtain mechanical fixing only by pressing.
In the present embodiment, the joint bump 9 and the cylindrical metal G have been described in detail for the conductive connection in the form in which the inner and outer surfaces of each other are rubbed together (connection form A1). However, when the elongated bonding bump 9 having a height d higher than the height h of the cylindrical metal G is pressed against the protective film 43 located at the bottom of the cylindrical metal G, the bonding bump 9 is deformed to form a cylinder. A form (connection form A2) of conductive connection to the inner surface of the metal G may be taken.

(Embodiment 2)
FIG. 8 is a cross-sectional view showing detection device 100 according to Embodiment 2 of the present invention. The present embodiment is characterized in that the p-side electrode includes a cylindrical metal G and a pad portion 11 that is a bottom conductive portion that closes the bottom of the cylindrical metal G. That is, the pad portion 11 that is in ohmic contact with the p-side region 6 and the cylindrical metal G that is integrally positioned thereon constitute a p-side electrode. In other words, it can be considered that the metal bottom 11 is added to the cylindrical metal G in the detection device 100 of the first embodiment shown in FIG. The protective film 43 is not disposed inside the cylindrical metal G. The other parts are the same as those in the first embodiment, and thus the description of the other parts is omitted.

Since the metal bottom 11 is provided on the cylindrical metal G, the form of conductive connection with the bonding bump 9 is facilitated by the connection form A2 in addition to the connection form A1 in which the side surfaces are rubbed together in the first embodiment. . Since the bonding bumps 9 have an elongated shape, a conductive connection mode that does not assume friction between the outer side surface and the inner side surface of the cylindrical metal G will be described below. FIG. 9 is a diagram showing the bonding bump 9 and the cylindrical metal G based on the connection form A2. The bonding bump 9 is set to be elongated by making its outer diameter smaller than the inner diameter of the cylindrical metal G. That is, d> h is preferable. FIG. 9A is a cross-sectional view showing a state where the tip end portion of the bonding bump 9 has reached the bottom portion 11 of the cylindrical metal G. FIG. The bonding bump 9 has an outer diameter considerably smaller than the inner diameter of the cylindrical metal G, and the bonding bump 9 is inserted into the cylindrical metal G with a margin. When pressure is applied to each other and pressed against each other, the bonding bumps 9 are widened by pressing the tip portion at the bottom of the cylindrical metal G. The tip of the bonding bump 9 does not have to bulge as shown in FIG. 9B, and it is sufficient if the contacted state as shown in FIG. 9A can be maintained. For this purpose, as shown in FIG. 9B, it is desirable to push in so far that the portion of the bonding bump 9 bulges to some extent. As a result, the bonding bump 9 and the cylindrical metal G or pad 11 are conductively connected with a low contact resistance.
The advantage in the present embodiment is that the outer diameter of the bonding bump 9 can be made smaller than the inner diameter of the cylindrical metal G. Due to this advantage, the bonding bump 9 is reliably accommodated and held in the cylindrical metal G. For this reason, even when a large number of bonding bumps 9 and cylindrical metal G are provided and their shapes and positions deviate from normal, the deviations are often absorbed and short-circuited with the adjacent pixels. And a hybrid structure can be formed.
Of course, by making the opening or inner diameter at the tip of the cylindrical metal G larger than the outer diameter of the tip of the bonding bump 9, the tip of the bonding bump 9 can be easily accommodated in the cylindrical metal G, and By making the outer diameter at the middle height position of the bonding bump 9 or the outer diameter at the base portion larger than the inner diameter at the middle height position of the cylindrical metal G, the outer surface of the bonding bump 9 is made cylindrical metal. You may make it rub against the inner surface of G.

  FIG. 10 is a diagram illustrating a pixel connection portion when the light receiving element array 50 has a curved surface, for example. Even when the light receiving element is tilted in this way, the combination of the cylindrical metal G and the pad 11 in the present embodiment is used, and the bonding pad 9 is elongated to make the readout electrode pad 71 and the pixel electrodes G and 11. Is easily realized in a normal one-to-one manner. As a result, it is possible to prevent a short circuit with an adjacent pixel and obtain high image quality or high resolution.

  In the present embodiment, even when the pad 11 is provided on the bottom of the cylindrical metal G, the connection of the connection form A1 can be established by setting the outer surface of the bonding bump 9 to rub against the inner diameter surface of the cylindrical metal G. Can take. Whether to use the connection form A1 or the connection form A2 is determined by comprehensively judging the degree of deformation of the light receiving element array 50 and the CMOS 70 (in-plane deformation, out-of-plane deformation accompanying thermal expansion, etc.), work accuracy, and the like. Is good. In that case, in order to realize the connection form A1, it is preferable to set the outer diameter of the bonding bump 9 to rub against the inner diameter of the cylindrical metal G, and in order to realize the connection form A2, the bonding bump 9 It is preferable to set the outer diameter of the cylindrical metal G to be small with a margin with respect to the inner diameter of the cylindrical metal G. The same applies to the structures of the following embodiments.

(Modification of Embodiment 2)
FIG. 11 is a cross-sectional view showing a detection apparatus 100 according to a modification of the second embodiment and showing an embodiment of the present invention. In this example, the cylindrical metal G is the same as the detection device 100 of FIG. 1 in the first embodiment in that it is in ohmic contact with the p-type region 6, but the protective film 43 in the cylindrical metal G is used. It differs in that the bottom plate 21 is disposed on the top. The connection with the bonding bump 9 is similar to the detection device 100 of FIG. 8 in the second embodiment in that the conductive portion is provided at the bottom of the cylindrical metal G. In this example, since the protective film 43 is disposed on the p-type region 6 and the bottom plate 21 of the cylindrical metal G is disposed thereon, the protective film 43 is compared with the structure of FIG. 8 in the second embodiment. It is different in that it is arranged. The other parts are the same as those of the detection device of FIG. 8 or FIG.

  The combination of the cylindrical metal G and the bottom plate 21 in FIG. 11 is not different from the combination of the cylindrical metal G and the pad 11 in FIG. Therefore, FIGS. 9A, 9B, and 10 apply to this example as they are, and the descriptions of FIGS. 9A, 9B, and 10 also correspond to this example as they are.

(Embodiment 3)
FIG. 12 is a cross-sectional view showing detection device 100 according to Embodiment 3 of the present invention. In the present embodiment, the cylindrical metal G is provided in the readout circuit 70 and the bonding bump 9 is provided in the pad 11 on the p-type region 6 of the light receiving element array 50 in FIG. Although different, other parts are the same as in FIG. In this case, since the pad 70 is provided in the CMOS 70, the bottom portion 71 is provided in the cylindrical metal G, and the description in FIGS. 8 to 11 in the second embodiment and the modifications thereof can be applied as it is. Can do.
For example, even when the light receiving element array 50 has a curved surface, the reading circuit 70, the light receiving element array 50, and the like can be obtained by using the cylindrical metal G and the pad 71 and elongating the bonding pad 9 in the present embodiment. It is easy to realize the connection in a normal one-to-one form for each pixel. As a result, it is possible to prevent a short circuit with an adjacent pixel and obtain high image quality or high resolution.

(Other embodiments)
In the above embodiment of the present invention, an example of a detection device without cooling using an InP-based light receiving element array that can be used at room temperature has been described. However, the present invention is not limited to this. You may use for MCT which cools. Further, the InP-based light receiving element array described in the embodiment of the present invention may be used in a detection device that performs cooling.

  Although the embodiments and examples of the present invention have been described above, the embodiments and examples of the present invention disclosed above are merely examples, and the scope of the present invention is the implementation of these inventions. It is not limited to the form. The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

  According to the detection apparatus and the like of the present invention, it is possible to obtain high image quality or high resolution because it is excellent in economic efficiency and enables a high production yield and does not cause a short circuit between adjacent pixels. This detection device or the like can detect a living body or the like using near-infrared light attracting attention in recent years without performing temperature control or the like.

  1 InP substrate, 2 buffer layer, 3 light receiving layer, 4 cap layer, 6 p-type region, 9 bonding bump, 9a bonding bump tip, 9b bonding bump root, 11 p side pad, 12 n side electrode, 14 diffusion concentration Distribution adjustment layer, 15 pn junction, 35 antireflection film, 36 selective diffusion mask pattern, 43 polyimide protective film, 49 gap between bonding bump tip and p-side electrode, 50 light receiving element array, 70 readout circuit, 71 readout electrode, 72 Ground electrode, 100 detection device, G cylindrical metal part, P pixel, b cylindrical metal root part, d bond pad height, h cylindrical metal height, t cylindrical metal tip.

Claims (15)

A light receiving element array in which a plurality of light receiving elements made of a compound semiconductor having light receiving sensitivity in the near infrared region are arranged;
A readout circuit for reading out photoelectric charges for each pixel;
A bonding bump interposed for each pixel between the light receiving element array and the readout circuit;
A cylindrical conductive member that is a cylindrical body that is conductively connected to the bonding bump,
The cylindrical conductive member is provided on one of the light receiving element array side and the readout circuit side, the bonding bump is provided on the other side where the cylindrical conductive member is not provided, and the cylindrical conductive member is The detection device is positioned so as to accommodate the bonding bump.   The detection apparatus according to claim 1, wherein an inner diameter of the cylindrical conductive member is larger than an outer diameter of the bonding bump.   The detection apparatus according to claim 1, wherein a height of the cylindrical conductive member is larger than a height of the bonding bump.   The detection apparatus according to claim 1, wherein the cylindrical conductive member has an inner diameter that increases from a root portion toward a tip.   The outer diameter of the bonding bump is smaller than the inner diameter at the tip of the cylindrical conductive member at the bump tip, and is equal to or larger than the inner diameter at the tip of the cylindrical conductive member at the bump root portion. The detection device according to any one of the above.   The detection apparatus according to claim 1, further comprising a bottom conductive portion that closes a bottom of the cylindrical conductive member.   The taper for reducing the inner diameter from the tip to the inner peripheral surface so as to reduce the thickness while leaving the outer peripheral surface side thin at the front end portion of the cylindrical conductive member. The detection device according to any one of 1 to 6.   The detection apparatus according to claim 1, wherein the cylindrical conductive member is an electrode of a pixel fixed to the light receiving element array.   The detection apparatus according to claim 1, wherein the cylindrical conductive member is a metal containing Zn and / or Pt.   The detection device according to claim 1, wherein the bonding bump includes In and / or Sn.   The light receiving element array includes an InP substrate and a light receiving layer having a band gap wavelength of 1.65 μm to 3.0 μm provided on the InP substrate, and the light receiving layer includes InGaAsNP, InGaAsNSb, and InGaAsN. The detection device according to claim 1, wherein the detection device is any one of them.   The light receiving element array includes an InP substrate and a light receiving layer having a band gap wavelength of 1.65 μm to 3.0 μm provided on the InP substrate, and the light receiving layer includes GaAsSb / InGaAs, GaAsSb / InGaAsN. The detection device according to claim 1, wherein the detection device has a type II type quantum well structure made of GaAsSb / InGaAsNP or GaAsSb / InGaAsNSb.   A sensor comprising the light receiving element array used in the detection device according to claim 1. A method of manufacturing a sensor of a light receiving element array in which a plurality of light receiving elements are arranged on a compound semiconductor having light receiving sensitivity in the near infrared region,
Forming a cylindrical electrode for each of the light receiving elements so as to be in ohmic contact with the light receiving element on the surface of the epitaxial layer of the compound semiconductor;
In the step of forming the cylindrical electrode, the cylindrical conductive member is formed by vapor deposition using a photolithography method, or is formed using a plating method after vapor deposition using the photolithography method. A method for manufacturing a sensor. Preparing a light receiving element array in which a plurality of light receiving elements are arranged on a compound semiconductor having light receiving sensitivity in the near infrared region;
Preparing a readout circuit for reading out photoelectric charges for each of the light receiving elements;
In the step of preparing the light receiving element array and the readout circuit, a cylindrical conductive member is formed on one of the electrode of the light receiving element and the electrode of the readout circuit,
Forming a bonding bump on the other side where the cylindrical conductive member is not formed,
The light receiving element array and the readout circuit are aligned to face each other, and (1) while applying pressure so that the bonding bump is accommodated in the cylindrical body, or (2) the bonding bump is the cylinder. The temperature is raised above the melting point of the bonding bump in the state of being accommodated in the cylindrical body, or (3) the temperature is higher than the melting point of the bonding bump while applying pressure so that the bonding bump is accommodated in the cylindrical body. The manufacturing method of a detection apparatus characterized by including the process of raising and joining.

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