JP2012189327A - Detection apparatus and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a detection apparatus which is capable of improving airtightness.SOLUTION: A detection apparatus 1 comprises a first substrate 2 having a detection element 21 and a second substrate 3 connected to the first substrate 2. The first substrate 2 further includes a first electrode 23 electrically connected with the detection element 21 and a first metal layer 26 laminated on a counter surface 201. The second substrate 3 includes a second electrode 33 connected with the first electrode 23 and a second metal layer 34 connected with the first metal layer 26. A surface 231 of the first electrode 23 and a surface 261 of the first metal layer 26 are positioned substantially on the same plane F1, and a surface 331 of the second electrode 33 and a surface 341 of the second metal layer 34 are also positioned substantially on the same plane F2. The second substrate 3 further includes an annular projection 32 which is positioned between the second electrode 33 and the second metal layer 34 and electrically insulates the second electrode 33 and the second metal layer 34.

Description

  The present invention relates to a detection device in which a detection element is packaged and a method for manufacturing the same.

  The bonding metal layer for connecting the sensor wafer having the sensing portion and the bonding metal layer for connecting the package wafer are bonded at room temperature, and the bonding metal layer for sealing the sensor wafer and the bonding metal layer for sealing the package wafer are bonded at room temperature. A joined sensor element is known (for example, see Patent Document 1).

JP 2007-171153 A

  In the sensor element described above, a space is formed between the bonding metal layer for connection and the bonding metal layer for sealing in the package wafer to insulate the two.

  However, since the package wafer and the sensor wafer cannot be bonded to each other in this space, the bonding area between the package wafer and the sensor wafer is reduced, and the airtightness in the sensor element cannot be sufficiently improved. It was.

  The problem to be solved by the present invention is to provide a detection device capable of improving airtightness and a method for manufacturing the same.

  According to the present invention, the second substrate has an annular protrusion located between the second electrode and the second metal layer and electrically insulating the second electrode and the second metal layer. To solve the above problem.

  According to the present invention, the annular protrusion is provided between the second electrode and the second metal layer, so that the annular protrusion is bonded to the first substrate in addition to the second electrode and the second metal layer. As a result, the bonding area of the first and second substrates can be increased, and the airtightness in the detection apparatus can be improved.

FIG. 1 is a plan view of a detection apparatus according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line II-II in FIG. FIG. 3 is an enlarged cross-sectional view of a portion III in FIG. FIG. 4 is an enlarged cross-sectional view of a portion IV in FIG. FIG. 5 is a cross-sectional view taken along the line VV in FIG. FIG. 6 is a cross-sectional view showing a first modification of the annular protrusion in the first embodiment of the present invention. FIG. 7 is a cross-sectional view showing a second modification of the annular protrusion in the first embodiment of the present invention. FIG. 8 is a cross-sectional view showing a third modification of the annular protrusion in the first embodiment of the present invention. FIG. 9 is a flowchart showing a method of manufacturing the detection device according to the first embodiment of the present invention. FIG. 10 is a cross-sectional perspective view showing the second substrate in the second step of FIG. 9 (No. 1). 11 is a cross-sectional view taken along line XI-XI in FIG. FIG. 12 is a cross-sectional perspective view showing the second substrate in the second step of FIG. 9 (No. 2). 13 is a cross-sectional view taken along line XIII-XIII in FIG. FIG. 14 is a cross-sectional perspective view showing the second substrate in the third step of FIG. 15 is a cross-sectional view taken along line XV-XV in FIG. FIG. 16 is a cross-sectional view showing the third step of FIG. FIG. 17 is a cross-sectional view showing the annular protrusion of the detection device according to the second embodiment of the present invention. FIG. 18 is a cross-sectional view showing an annular protrusion in the third step in the second embodiment of the present invention. FIG. 19 is a plan view of the annular protrusion of FIG. 18 viewed from the lower surface side. FIG. 20 is a cross-sectional view showing the annular protrusion and the auxiliary protrusion of the detection device according to the third embodiment of the present invention. 21 is a cross-sectional view taken along line XXI-XXI in FIG. FIG. 22 is a cross-sectional view showing the annular protrusion and the auxiliary protrusion in the third step in the third embodiment of the present invention. FIG. 23 is a cross-sectional view showing the annular protrusion and the auxiliary protrusion of the detection device according to the fourth embodiment of the present invention. 24 is a cross-sectional view taken along line XXIV-XXIV in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<< first embodiment >>
1 is a plan view of the detection apparatus according to the present embodiment, FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1, FIG. 3 is an enlarged cross-sectional view of a portion III in FIG. FIG. 5 is a cross-sectional view taken along line VV in FIG. 4, and FIGS.

  The detection apparatus 1 in this embodiment is an apparatus used to detect, for example, night vision or human body temperature, and includes a plurality of infrared sensors 22 as shown in FIGS. 1 and 2. The first substrate 2 and the second substrate 3 are joined and the infrared sensor 22 is packaged between them. Note that an image sensor or the like may be packaged instead of the infrared sensor.

  As shown in FIGS. 3 and 4, the first substrate 2 includes the first substrate body 20, the infrared sensor 22 described above, the first electrode 23, the wiring metal 24, the insulating layer 25, 1 metal layer 26.

  The first substrate body 20 is a substrate made of, for example, silicon (Si), and has a first facing surface 201 that faces the second substrate 3. A first recess 21 is formed in the first facing surface 201.

  As shown in FIGS. 2 and 3, the first recess 21 is located below the infrared sensor 22 on the first facing surface 201 and thermally insulates the infrared sensor 22 and the first substrate body 20 from each other. is doing.

  When the infrared sensor 22 receives infrared rays and the temperature rises, the infrared sensor 22 converts the temperature rise into an electrical signal. Examples of the infrared sensor 22 include a bolometer and a thermistor.

  As shown in FIG. 3, the infrared sensor 22 is disposed in the opening portion of the first recess 21 in the central portion of the first facing surface 201. The infrared sensor 22 is supported by a support beam (not shown) so as not to be in contact with the first facing surface 201, the bottom surface of the first recess 21, and the wall surface. The number of infrared sensors 22 is not particularly limited.

  The first electrode 23 is an electrode that outputs an electrical signal output from the infrared sensor 22 to a second electrode 33 (described later) of the second substrate 3 via the wiring metal 24. For example, copper (Cu ), Aluminum (Al), gold (Au), and other metals. As shown in FIG. 4, the first electrode 23 is connected to the wiring metal 24 in the insulating layer 25.

  The surface 231 of the first electrode 23 is exposed from the insulating layer 25, is flattened at the atomic level, and is bonded to the second electrode 33 of the second substrate 3 at room temperature (surface activated bonding). Yes.

  The wiring metal 24 shown in FIG. 4 is a member that electrically connects the infrared sensor 22 and the first electrode 23, and is electrically connected to the infrared sensor 22, although not particularly illustrated. The wiring metal 24 is made of, for example, copper or aluminum.

As shown in FIG. 4, the insulating layer 25 is laminated on the first facing surface 201, and the surface 251 of the insulating layer 25 is formed so as to correspond to the tip surface 321 of the annular protrusion 32 described later. . The insulating layer 25 is made of, for example, silicon dioxide (SiO ₂ ), and electrically insulates the first electrode 23 and the first metal layer 26.

  The first metal layer 26 seals a space 311 formed between the second recess 31 described later and the first facing surface 201 together with the second metal layer 34 (described later) of the second substrate 3. is doing. The surface 261 of the first metal layer 26 is flattened at the atomic level, and is bonded to the surface 341 of the second metal layer 34 by room temperature bonding.

  As shown in FIG. 4, the surface 261 of the first metal layer 26 is located on the same plane F <b> 1 as the surface 231 of the first electrode 23 and the surface 251 of the insulating layer 25. Further, since the first electrode 23, the insulating layer 25, and the first metal layer 26 are in close contact with each other on the plane F1, the plane F1 is continuously flat.

  The first metal layer 26 in the present embodiment is made of the same metal as the first electrode 23 such as copper, aluminum, or gold.

  The second substrate 3 is a substrate that stores the infrared sensor 22 between the first substrate 2 and transmits infrared rays irradiated to the infrared sensor 22. As shown in FIGS. 2 to 4, the second substrate 3 has a second substrate body 30, a second electrode 33, and a second metal layer 34.

  The second substrate body 30 is made of zinc sulfide (ZnS) that can transmit infrared rays, and has a second facing surface 301 that faces the first substrate 2. A second concave portion 31 and an annular protrusion 32 are formed on the second facing surface 301.

  As shown in FIGS. 2 and 3, the second recess 31 is formed on the second facing surface 301 so as to surround the plurality of infrared sensors 22 together. The second recess 31, together with the first facing surface 201 of the first substrate 2, defines a space 311 that accommodates the infrared sensor 22. Note that the space 311 is in a vacuum state where the pressure is lower than that of the atmosphere.

  A convex lens-shaped microlens 312 is formed on the bottom surface of the second recess 31 at a portion facing the infrared sensor 22. In the present embodiment, infrared light can be condensed on the infrared sensor 22 by the micro lens 312. A dotted line in FIG. 3 indicates an infrared path that passes through the second substrate 3 and is collected by the infrared sensor 22.

  As shown in FIGS. 4 and 5, the annular protrusion 32 is a protrusion formed on the second facing surface 301 so as to surround the second electrode 33. Located between the metal layers 34, the second electrode 33 and the second metal layer 34 are electrically insulated. In the present embodiment, the annular protrusion 32 has a ring-shaped tip surface 321 (cross-sectional shape), but the tip surface 321 is not particularly limited, and may be, for example, a rectangular frame.

  Further, as shown in FIG. 4, the outer peripheral surface 322 of the annular protrusion 32 is a tapered inclined surface inclined at an angle θ with respect to the thickness direction A of the second substrate 3. W is continuously narrowed from the second facing surface 301 toward the tip surface 321 of the annular protrusion 32.

  In this embodiment, only the outer peripheral surface 322 of the annular protrusion 32 is a tapered slope, but as shown in FIG. 6, both the inner peripheral face 323 and the outer peripheral face 322 may be tapered slopes. Alternatively, as illustrated in FIG. 7, the outer peripheral surface 322 may not be inclined with respect to the thickness direction A, and only the inner peripheral surface 323 may be a tapered inclined surface.

  Further, as shown in FIG. 8, the outer peripheral surface 322 may be inclined so that the angle θ changes with a predetermined curvature. Similarly, although not particularly illustrated, when the inner peripheral surface of the annular protrusion is a slope, the inner peripheral surface may be inclined so that the angle θ changes with a predetermined curvature.

  As shown in FIG. 3, the second electrode 33 outputs the electrical signal input from the first electrode 23 to the outside of the detection device 1 through the through hole 35 formed in the second substrate 3. Electrode. In the present embodiment, as shown in FIG. 1, the number of second electrodes 33 corresponding to the first electrodes 23 is provided on the second substrate 3.

  As shown in FIGS. 3 and 4, the second electrode 33 is disposed so as to face the first electrode 23 of the first substrate 2, and the surface 331 is planarized at the atomic level (for example, The arithmetic average roughness Ra is about 2 nm) and is bonded to the surface 231 of the first electrode 23 at room temperature as described above. The second electrode 33 is made of the same metal as the first electrode 23 such as copper, aluminum, or gold.

  The second metal layer 34 seals the space 311 formed between the second recess 31 and the first facing surface 201 together with the first metal layer 26. The surface 341 of the second metal layer 34 is flattened at the atomic level and bonded to the first metal layer 26 of the first substrate 2 at room temperature.

  As shown in FIG. 4, the surface 341 is located on the same plane F <b> 2 as the tip surface 321 of the annular protrusion 32 and the surface 331 of the second electrode 33. Further, since the annular protrusion 32, the second electrode 33, and the second metal layer 34 are in close contact with each other on the plane F2, the plane F2 is continuously flat.

  The second metal layer 34 in the present embodiment is made of a metal such as copper, aluminum, or gold, for example. In the present embodiment, the metal constituting the second metal layer 34 is the same metal as the first electrode 23, the first metal layer 26, and the second electrode 33.

  Next, the manufacturing method of the detection apparatus 1 in this embodiment is demonstrated.

  FIG. 9 is a flowchart showing a manufacturing method of the detection device in the present embodiment, FIG. 10 is a cross-sectional perspective view showing the second substrate in the second step of FIG. 9, and FIG. 11 is taken along the line XI-XI in FIG. 12 is a sectional perspective view showing the second substrate in the second step of FIG. 9, FIG. 13 is a sectional view taken along line XIII-XIII of FIG. 12, and FIG. 14 is a third step of FIG. FIG. 15 is a sectional view taken along line XV-XV in FIG. 14, and FIG. 16 is a sectional view showing a third step in FIG. 10 to 15, the second facing surface 301 is shown facing upward in the drawing.

  As shown in FIG. 9, the manufacturing method of the detection apparatus 1 in the present embodiment includes a first step S10, a second step S20, a third step S30, and a fourth step S40. Yes.

  The first step S <b> 10 is electrically connected to the first substrate body 20 in which the first recess 21 is formed, the infrared sensor 22 disposed in the opening portion of the first recess 21, and the infrared sensor 22. In this step, the first substrate 2 having the first electrode 23 and the first metal layer 26 is prepared. In the first substrate 2 prepared in the first step S10, the surface 261 of the first metal layer 26 and the surface 231 of the first electrode 23 are located on substantially the same plane F1. Yes. The first recess 21 is formed, for example, by etching the first substrate body 20.

  The second step S <b> 20 is a step of preparing the second substrate 3 having the second substrate body 30, the second electrode 33, and the second metal layer 34.

  This second step S20 includes a substrate forming step and a plating step.

  As shown in FIGS. 10 and 11, the substrate forming step includes a second recess 31 having a microlens 312 on the bottom surface, an annular protrusion 32, and a through-hole 35 positioned at a substantially central portion of the annular protrusion 32. This is a step of forming the second substrate body 30 having the same.

  In this substrate molding step, for example, in a state where the molding die is filled with powdered zinc sulfide (ZnS) as the material of the second substrate body 30 and pressed at a pressure of several tens of MPa to about 1000 degrees. The second substrate body 30 is formed by sintering zinc sulfide by heating for about 5 minutes. The second substrate body 30 may be molded by depositing a thin film in a molding die by a CVD (Chemical Vapor Deposition) method.

  As described above, the second substrate body 30 in a state formed by the sintering method or the CVD method includes the second concave portion 31 having the microlens 312 and the projection of the truncated cone that becomes the annular projection 32. ing. In this embodiment, the central portion of the projection of the truncated cone is drilled to form the through hole 35 in the second substrate body 30 and the projection is formed in an annular shape (annular projection 32) from the truncated cone.

  In the plating step, as shown in FIGS. 12 and 13, the microlens 312 is covered with a protective film 50, and the entire second substrate body 30 is electrolessly plated. Next, the second substrate body 30 is electrolytically plated. Thus, the plating layers 41 and 42 are laminated on both surfaces of the second substrate body 30 to form the second metal layer 34, and the inside of the through hole 35 is filled with the plating material, so that the second electrode 33 is formed. Examples of the plating material include metals such as copper, aluminum, and gold.

  In the third step S30, as shown in FIGS. 14 and 15, the plating layer 42 laminated on the main surface 302 of the second substrate body 30 is lapped and polished to expose the main surface 302. Further, the plating layer 41 laminated on the second facing surface 301 of the second substrate body 30 is lapped and polished so that the tip surface 321 of the annular protrusion 32 is exposed from the plating layer 41, and the second electrode 33 and The second metal layer 34 is electrically insulated.

  At this time, the arithmetic average roughness Ra of the surface 331 of the second electrode 33 and the surface 341 of the second metal layer 34 is finished to about 2 nm, and the distance L2 from the microlens 312 to the plane F2 is set to the design value. On the other hand, finishing is performed within a predetermined range (for example, ± 15 μm).

  In the present embodiment, since the width W of the annular protrusion 32 continuously increases from the tip surface 321 toward the second facing surface 301, the width of the tip surface 321 is proportional to the lapping amount and the polishing amount. W becomes wider.

  For this reason, in this embodiment, it is possible to determine the amount of lapping and polishing the annular protrusion 32, the second electrode 33, and the second metal layer 34 based on the width W of the distal end surface 321. . For example, when the angle θ (see FIG. 4) of the outer peripheral surface 322 of the annular protrusion 32 is 45 degrees, the width W of the tip surface 321 of the annular protrusion 32 is increased by 10 μm by lapping and polishing. 32, the second electrode 33 and the second metal layer 34 can be determined to have been cut by 10 μm.

  Here, the polishing step in the third step S30 will be described. As shown in FIG. 16, the second substrate 3 is fixed to the jig 63 using the WAX 62 and pressed against the rotating polishing pad 61. A chiller 60 is applied on the polishing pad 61.

  When the flat surface F2 is polished in this polishing step, a light emitting device 64 that emits light toward the annular protrusion 32 is attached to the jig 63 as shown in FIG. As a result, the portion of the polishing pad 61 that faces the annular protrusion 32 is irradiated with light from the light emitting device 64 that has passed through the annular protrusion 32. On the other hand, since the second electrode 33 and the second metal layer 34 cannot transmit light, the portion of the polishing pad 61 that faces the second electrode 33 and the second metal layer 34 has light of the light emitting device 64. Is not irradiated.

  If polishing is performed in such a state, as described above, the image of the light applied to the polishing pad 61 as the width W of the tip surface 321 of the annular protrusion 32 increases in proportion to the polishing amount. The area (annular line width) is also increased. In the present embodiment, it is possible to determine whether or not a predetermined polishing amount has been reached by performing visual confirmation or image analysis using a camera on the area (annular line width) of the light image.

  Specifically, during the polishing process, the second substrate 3 is once separated from the polishing pad 61 together with the jig 63, and an image of light irradiated on the polishing pad 61 is confirmed visually or with a camera. When the area (width) of the light image has not reached the predetermined value and the polishing amount has not reached the predetermined amount, the second substrate 3 is again pressed against the polishing pad 61 through the jig 63 for polishing. To continue. As described above, in this embodiment, it is not necessary to remove the substrate from the jig in order to check the polishing processing status, so that the number of steps in the polishing process can be reduced.

  The method for confirming the processing status of polishing is not limited to the above method. For example, the light of the light emitting device reflected by the second metal layer may be monitored.

  In the fourth step S40, the first and second metal layers 26 and 34 are bonded at room temperature with the infrared sensor 22 and the microlens 312 facing each other, and the first and second electrodes 23 and 33 are bonded at room temperature. Join. At this time, the space 311 formed between the first and second substrates 2 and 3 is sealed in a vacuum state in which the pressure is reduced from the atmospheric pressure.

  Next, the operation of this embodiment will be described.

  In the present embodiment, an annular protrusion 32 is provided between the second electrode 33 and the second metal layer 34. In addition to exhibiting the function of insulating the second electrode 33 and the second metal layer 34, the annular protrusion 32 serves as a joint surface with the first substrate 2 for the tip surface 321 of the annular protrusion 32. Is also functioning.

  In the present embodiment, since the entire surface F2 of the second substrate 3 can be bonded to the first substrate 2 by the annular protrusion 32, the bonding area of the first and second substrates 2 and 3 is increased. It becomes possible. Thereby, the airtightness of the space 311 can be improved, and the reliability as a package in the detection apparatus 1 can be improved.

  Further, by providing the annular protrusion 32 on the second substrate 3, the plane F <b> 2 constituted by the tip surface 321 of the annular protrusion 32, the surface 331 of the second electrode 33, and the surface 341 of the second metal layer 34 is It becomes flat continuously. As a result, when the flat surface F2 is lapped and polished (planarized) for the above-described room temperature bonding, surface sagging or chipping occurs at the edge portions of the second electrode 33 or the second metal layer 34. This can prevent the area of the joint surface between the first and second substrates 2 and 3 from becoming narrow.

  Here, when performing such lapping or polishing, it is necessary to cover the microlens 312 with the protective film 50 (see FIGS. 12 to 15) in order to protect the microlens 312. For this reason, it is impossible to directly measure the distance L2 (see FIG. 15) from the microlens 312 to the plane F2 while lapping or polishing is being performed.

  On the other hand, in the present embodiment, the width W of the annular protrusion 32 continuously increases from the front end surface 321 toward the second facing 301. For this reason, when lapping and polishing the second electrode 33, the second metal layer 34, and the annular protrusion 32, the width W of the tip surface 321 of the annular protrusion 32 is increased in proportion to the lapping amount and the polishing amount. Become.

  Thus, the distance L2 can be estimated by measuring the width W of the annular protrusion 32 without directly measuring the distance L2 from the microlens 312 to the plane F2. That is, in the present embodiment, the lapping amount and the polishing amount in the second electrode 33, the second metal layer 34, and the annular protrusion 32 can be determined based on the width W of the tip end surface 321 of the annular protrusion 32. It has become. By determining the lapping amount and the polishing amount by such a method, lapping and polishing can be performed accurately without being affected by the variation in the thickness of the plating layer 41.

  As described above, since the lapping amount and the polishing amount in the annular protrusion 32, the second electrode 33, and the second metal layer 34 can be determined, the first and second substrates 2 and 3 are joined as shown in FIG. In this state, the distance L1 from the micro lens 312 to the infrared sensor 22 can be accurately finished with respect to the design value. As a result, infrared rays can be concentrated on the infrared sensor 22 and the sensitivity of the infrared sensor 22 can be improved.

  In the present embodiment, as shown in FIG. 4, the outer peripheral surface 322 of the annular protrusion 32 is a tapered slope, but as shown in FIG. 8, the outer peripheral surface 322 of the annular protrusion 32 is inclined with a predetermined curvature. In such a case, the curvature may increase at a height near the design value. As a result, when lapping or polishing, the way in which the width W of the front end surface 321 widens becomes prominent near the design value, so that it is easy to understand that a predetermined lapping amount or polishing amount has been reached, and the accuracy of lapping or polishing is increased. Can be improved.

  Here, in the present embodiment, as described above, the first and second electrodes are bonded by room temperature bonding, but the first and second electrodes are exposed in the space inside the semiconductor device, It is also possible to join both via bumps. However, according to this method, variations in bump height and electrode height cannot be corrected, and stress is easily generated between the first and second substrates when the first and second substrates are joined.

  In contrast, in the present embodiment, the surface 231 of the first electrode 23 and the surface 261 of the first metal layer 26 are collectively lapped and polished, so that the surface 231 of the first electrode 23 and the first The surface 261 of the metal layer 26 is positioned on the substantially same plane F1. Further, lapping and polishing the surface 331 of the second electrode 33 and the surface 341 of the second metal layer 34 together, the surface 331 of the second electrode 33 and the surface 341 of the second metal layer 34 are obtained. , They are positioned on substantially the same plane F2. Accordingly, in the present embodiment, the first and second electrodes 23 and 33 and the first and second metal layers 26 and 34 are reduced in height variation and the first and second electrodes 23 and 33 are reduced in height variation. It is difficult to generate stress between the two substrates 2 and 3.

  In the present embodiment, the first and second substrates 2 and 3 are bonded at room temperature to reduce the residual stress generated in the first and second substrates 2 and 3 at the time of bonding. Has improved.

  Here, in order to perform room temperature bonding, it is necessary to planarize the substrates at the atomic level. In the present embodiment, even if the first and second substrates 2 and 3 themselves cannot be planarized at the atomic level, the first and second metal layers 26 and 34 that can be planarized at the atomic level are provided. Thus, the first and second substrates 2 and 3 can be bonded at room temperature.

  In this embodiment, since the first and second substrates 2 and 3 are joined and the space 311 is sealed in a vacuum state, the infrared sensor 22 can be protected from external impact and dust. At the same time, moisture absorption by the infrared sensor 22 can be suppressed.

  Further, in the present embodiment, since packaging at the wafer level is possible, the manufacturing cost of the detection apparatus 1 can be reduced.

<< Second Embodiment >>
Next, a second embodiment of the present invention will be described.

  FIG. 17 is a cross-sectional view showing the annular protrusion of the detection device in this embodiment, FIG. 18 is a cross-sectional view showing the annular protrusion in the third step in this embodiment, and FIG. 19 is a view of the annular protrusion in FIG. It is a top view.

  In the present embodiment, the shape of the annular protrusion 32a is different from that of the first embodiment, but other configurations are the same as those of the first embodiment. Below, only the part which is different from 1st Embodiment is demonstrated about the detection apparatus 1a in this embodiment, About the part same as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the present embodiment, as shown in FIG. 17, the width W of the annular protrusion 32a is gradually reduced from the second facing surface 301 toward the distal end surface 321a. That is, the outer peripheral surface 322a of the second annular protrusion 32a is formed in a step shape.

  Also in this embodiment, by providing the annular protrusion 32a between the second electrode 33 and the second metal layer 34, the bonding area of the first and second substrates 2 and 3 is increased. Thereby, the airtightness of the space 311 can be improved, and the reliability as a package in the detection apparatus 1a can be improved.

  Next, the manufacturing method of the detection apparatus 1a in this embodiment is demonstrated.

  In the third step S30 in the present embodiment, as the annular protrusion 32a is lapped and polished, the width W of the annular protrusion 32a exposed from the second metal layer 34 gradually increases as shown in FIG. In FIGS. 18 and 19, it can be seen that when the annular protrusion 32a is cut from the surface 321a to the depth of H1, the width W is changed from W0 to W1, and further when it is cut to the depth of H2, the width W is changed to W2. Thereby, for example, it is understood that lapping and polishing for H1 have been executed when the width W of the annular protrusion 32a is changed from W0 to W1. Alternatively, when the width W of the line end surface 321a of the annular protrusion 32a becomes W1, it can be confirmed that the predetermined lapping amount and polishing amount have been reached.

  Thus, also in this embodiment, the wrapping amount is based on the width W of the tip end surface 321a of the annular protrusion 32a without directly measuring the distance L2 (see FIG. 15) from the microlens 312 to the plane F2. And the amount of polishing can be determined.

  Thus, the distance L2 can be accurately realized with respect to the design value, and the distance L1 from the microlens 312 to the infrared sensor 22 in the state where the first and second substrates 2 and 3 are joined (see FIG. 3) can be accurately finished with respect to the design value. As a result, infrared rays can be concentrated on the infrared sensor 22 and the sensitivity of the infrared sensor 22 can be improved.

  Further, similarly to the first embodiment, in the present embodiment, it is possible to check the polishing processing state in a state where the second substrate 3 is fixed to the jig 63. Man-hours can be reduced.

  Similarly to the first embodiment, in this embodiment, the plane F2 is continuously flat. Therefore, in the third step S30, the second electrode 33 and the second metal layer 34 are removed. It is possible to prevent the sag or chipping at the edge portion. Thereby, also in this embodiment, it is suppressed that the area of the joint surface in the 1st and 2nd board | substrates 2 and 3 becomes narrow.

  Similarly to the first embodiment, in the present embodiment, the surface 231 of the first electrode 23 and the surface 261 of the first metal layer 26 are located on the substantially same plane F1, and the second The surface 331 of the electrode 33 and the surface 341 of the second metal layer 34 are positioned on substantially the same plane F2, and the first and second substrates 2 and 3 are joined by bumpless. Thereby, the variation in the height of the first and second electrodes 23 and 33 and the variation in the height of the first and second metal layers 26 and 34 are reduced, and the first and second substrates 2 and 3 are reduced. Stress is less likely to occur between the two.

  Similarly to the first embodiment, in this embodiment, the first and second substrates 2 and 3 are bonded at room temperature, so that the residual stress generated in the first and second substrates 2 and 3 at the time of bonding is reduced. The reliability of the package is improved. Also in this embodiment, by providing the first and second metal layers 26 and 34 that can be flattened at the atomic level, room temperature bonding between substrates that cannot be flattened at the atomic level is possible.

  Also in this embodiment, since the first and second substrates 2 and 3 are joined and the space 311 is sealed in a vacuum state, the infrared sensor 22 can be protected from external impact and dust. In addition, moisture absorption by the infrared sensor 22 can be suppressed.

  Also in the present embodiment, since packaging at the wafer level is possible, the manufacturing cost of the detection apparatus 1a can be reduced.

<< Third Embodiment >>
Next, a third embodiment of the present invention will be described.

  20 is a cross-sectional view showing the annular protrusion and the auxiliary protrusion of the detection device in the present embodiment, FIG. 21 is a cross-sectional view taken along line XXI-XXI in FIG. 20, and FIG. It is sectional drawing which shows an auxiliary protrusion.

  In the present embodiment, the point that the annular protrusion 32b is formed in a cylindrical shape and the point that auxiliary protrusions 36a and 36b are provided on the second substrate 3 in addition to the annular protrusion 32b are the same as in the first embodiment. Although different, other configurations are the same as those in the first embodiment. Below, only the part which is different from 1st Embodiment is demonstrated about the detection apparatus 1b in this embodiment, About the part same as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the present embodiment, as shown in FIG. 20, auxiliary projections 36 a and 36 b are provided on the second facing surface 301 of the second substrate body 30 in addition to the annular projection 32 b. The auxiliary projections 36a and 36b are both provided at positions away from the annular projection 32b.

  The height of the auxiliary protrusion 36a is substantially the same as that of the annular protrusion 32b when the detection device 1b is completed, and the tip surface 361a of the auxiliary protrusion 36a is exposed from the second metal layer 34. is doing. On the other hand, before the auxiliary protrusion 36a is lapped and polished, the height of the auxiliary protrusion 36a is lower than the annular protrusion 32b as shown in FIG.

  On the other hand, as shown in FIG. 21, the height of the auxiliary protrusion 36b is slightly lower than the annular protrusion 32b and the auxiliary protrusion 36a, and the front end surface 361b of the auxiliary protrusion 36b is slightly exposed from the second metal layer 34. It has become a state. That is, the front end surface 361b of the auxiliary projection 36b in the present embodiment includes a lower portion than the front end surface 321b of the annular projection 32b.

  In the present embodiment, as described above, the two auxiliary protrusions 36a and 36b are formed on the second substrate 3. However, the number of auxiliary protrusions is not particularly limited, and may be, for example, three or more. Good.

  Also in the present embodiment, by providing the annular protrusion 32b between the second electrode 33 and the second metal layer 34, the area of the bonding surface of the first and second substrates 2 and 3 is increased. Yes. Thereby, the airtightness of the space 311 can be improved, and the reliability as a package in the detection apparatus 1b can be improved.

  Next, the manufacturing method of the detection apparatus 1b in this embodiment is demonstrated.

  In the second step S20 in the present embodiment, the second substrate body 30 is formed by a sintering method or a CVD method using a molding die in which concave portions corresponding to the auxiliary protrusions 36a and 36b are formed.

  In the third step S30 in the present embodiment, as shown in FIG. 22, when lapping and polishing to H3, the tip surface 361a of the auxiliary projection 36a is exposed from the second metal layer 34, and further lapping and polishing to H4. Then, the front end surface 361 b of the auxiliary protrusion 36 b is exposed from the second metal layer 34.

  In the present embodiment, for example, it can be confirmed that a predetermined lapping amount or polishing amount has been reached based on the state in which the auxiliary protrusion 36b starts to be exposed from the second metal layer 34. In this case, it is understood that the remaining L3 (L3 = H4-H3) may be lapped and polished at the stage where the tip surface 361a of the auxiliary protrusion 36a is exposed from the second metal layer 34.

  That is, in the present embodiment, the distance L2 (see FIG. 15) from the microlens 312 to the plane F2 is not directly measured, but should be cut based on the exposed areas (exposed patterns) of the tip surfaces 361a and 361b. It is possible to determine the lapping amount and the polishing amount.

  Thereby, the distance L1 (see FIG. 3) from the microlens 312 to the infrared sensor 22 can be accurately finished with respect to the design value. As a result, the infrared rays can be concentrated on the infrared sensor 22 and the sensitivity of the infrared sensor 22 can be improved.

  Further, similarly to the first embodiment, in the present embodiment, it is possible to check the polishing processing state in a state where the second substrate 3 is fixed to the jig 63. Man-hours can be reduced.

  Similarly to the first embodiment, since the plane F2 is continuously flat in the present embodiment, the second electrode 33 and the second metal layer 34 are used in the third step S30. It is possible to prevent the occurrence of sagging or chipping at the edge portion of the sheet. Thereby, also in this embodiment, it is suppressed that the junction area of the 1st and 2nd board | substrates 2 and 3 becomes narrow.

  Similarly to the first embodiment, in the present embodiment, the surface 231 of the first electrode 23 and the surface 261 of the first metal layer 26 are located on the substantially same plane F1, and the second The surface 331 of the electrode 33 and the surface 341 of the second metal layer 34 are positioned on substantially the same plane F2, and the first and second substrates 2 and 3 are joined by bumpless. Thereby, the variation in the height of the first and second electrodes 23 and 33 and the variation in the height of the first and second metal layers 26 and 34 are reduced, and the first and second substrates 2 and 3 are reduced. Stress is less likely to occur between the two.

  Similarly to the first embodiment, in this embodiment, the first and second substrates 2 and 3 are bonded at room temperature, so that the residual stress generated in the first and second substrates 2 and 3 at the time of bonding is reduced. The reliability of the package is improved. Also in this embodiment, by providing the first and second metal layers 26 and 34 that can be flattened at the atomic level, room temperature bonding between substrates that cannot be flattened at the atomic level is possible.

  Also in this embodiment, since the first and second substrates 2 and 3 are joined and the space 311 is sealed in a vacuum state, the infrared sensor 22 can be protected from external impact and dust. In addition, moisture absorption by the infrared sensor 22 can be suppressed.

Also in this embodiment, since packaging at the wafer level is possible, the manufacturing cost of the detection apparatus 1b can be reduced.

<< Fourth embodiment >>
Next, a fourth embodiment of the present invention will be described.

  FIG. 23 is a cross-sectional view showing the annular protrusion and the auxiliary protrusion of the detection device in this embodiment, and FIG. 24 is a cross-sectional view taken along the line XXIV-XXIV in FIG.

  This embodiment differs from the first embodiment in that the annular protrusion 32c is formed in a cylindrical shape and in that an auxiliary protrusion 36c is provided on the second substrate 3 in addition to the annular protrusion 32c. However, other configurations are the same as those in the first embodiment. Below, only the part which is different from 1st Embodiment is demonstrated about the detection apparatus 1c in this embodiment, About the part same as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In this embodiment, as shown in FIGS. 23 and 24, an auxiliary projection 36c surrounding the annular projection 32c is provided outside the annular projection 32c. The tip surface 361c of the auxiliary protrusion 36c is exposed from the second metal layer 34 at about two-thirds of the entire tip surface 361c, and about one-third of the entire tip surface 361c is second. The metal layer 34 is covered. That is, the front end surface 361c of the auxiliary projection 36c in the present embodiment includes a portion lower than the front end surface 321c of the annular projection 32c.

  The auxiliary protrusion 36c in the present embodiment is formed such that the front end surface 361c is spirally lowered from the front end 361d toward the end 361e before being lapped or polished.

  In the present embodiment, the auxiliary protrusion 36c is formed so as to surround the annular protrusion 32c. However, the auxiliary protrusion 36c is not particularly limited. For example, the auxiliary protrusion 36c may be linearly formed.

  Also in the present embodiment, by providing the annular protrusion 32c between the second electrode 33 and the second metal layer 34, the bonding area of the first and second substrates 2 and 3 is increased. Thereby, the airtightness of the space 311 can be improved, and the reliability as a package in the detection apparatus 1c can be improved.

  Next, the manufacturing method of the detection apparatus 1c in this embodiment is demonstrated.

  In the second step S20 in the present embodiment, the second substrate body 30 is formed by a sintering method or a CVD method using a molding die in which a recess corresponding to the auxiliary protrusion 36c is formed.

  In the third step S30 in the present embodiment, as the flat surface F2 is lapped and polished, the front end surface 361c of the auxiliary projection 36c starts to be exposed from the front end 361d, and from the second metal layer 34 to the right in FIG. It is gradually exposed.

  For this reason, in this embodiment, even if the distance L2 (see FIG. 15) from the microlens 312 to the plane F2 is not directly measured, the area and shape (pattern) of the tip surface 361c exposed from the second metal layer 34 are measured. ) And the lapping amount and the polishing amount can be determined.

  Thereby, the distance L1 (see FIG. 3) from the microlens 312 to the infrared sensor 22 can be accurately finished with respect to the design value. As a result, the infrared rays can be concentrated on the infrared sensor 22 and the sensitivity of the infrared sensor 22 can be improved.

The method for determining the lapping amount and the polishing amount is not limited to the above method, and for example, the straight line connecting the tip 361d and the center O of the auxiliary projection 36c and the tip surface 361c are exposed from the second metal layer 34. The lapping amount and the polishing amount may be determined based on the angle B formed by the straight line connecting the end 361f of the portion and the center O.

  Further, similarly to the first embodiment, in the present embodiment, it is possible to check the polishing processing state in a state where the second substrate 3 is fixed to the jig 63. Man-hours can be reduced.

  Similarly to the first embodiment, in this embodiment, the plane F2 is continuously flat. Therefore, in the third step S30, the second electrode 33 and the second metal layer 34 are removed. It is possible to prevent the sag or chipping at the edge portion. Thereby, also in this embodiment, it is suppressed that the junction area of the 1st and 2nd board | substrates 2 and 3 becomes narrow.

  Similarly to the first embodiment, in the present embodiment, the surface 231 of the first electrode 23 and the surface 261 of the first metal layer 26 are located on the substantially same plane F1, and the second The surface 331 of the electrode 33 and the surface 341 of the second metal layer 34 are positioned on substantially the same plane F2, and the first and second substrates 2 and 3 are joined by bumpless. Thereby, the variation in the height of the first and second electrodes 23 and 33 and the variation in the height of the first and second metal layers 26 and 34 are reduced, and the first and second substrates 2 and 3 are reduced. Stress is less likely to occur between the two.

  Similarly to the first embodiment, in this embodiment, the first and second substrates 2 and 3 are bonded at room temperature, so that the residual stress generated in the first and second substrates 2 and 3 at the time of bonding is reduced. The reliability of the package is improved. Also in this embodiment, by providing the first and second metal layers 26 and 34 that can be flattened at the atomic level, room temperature bonding between substrates that cannot be flattened at the atomic level is possible.

  Also in this embodiment, since the first and second substrates 2 and 3 are joined and the space 311 is sealed in a vacuum state, the infrared sensor 22 can be protected from external impact and dust. In addition, moisture absorption by the infrared sensor 22 can be suppressed.

  Also in the present embodiment, since packaging at the wafer level is possible, the manufacturing cost of the detection apparatus 1c can be reduced.

  The infrared sensor 22 in the first to fourth embodiments corresponds to an example of the detection element in the present invention, and the second recess 31 in the first to fourth embodiments corresponds to an example of the recess in the present invention.

  The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c ... Detection apparatus 2 ... 1st board | substrate 20 ... 1st board | substrate body 22 ... Infrared sensor 23 ... 1st electrode 26 ... 1st metal layer 3 ... 2nd board | substrate 30 ... 2nd Substrate body 31 ... second recess 311 ... space 312 ... micro lens 32, 32a, 32b, 32c ... annular protrusion 321 ... tip surface 322 ... outer peripheral surface 323 ... inner peripheral surface 33 ... second electrode 34 ... second electrode Metal layer 36a, 36b, 36c ... auxiliary protrusion

Claims (7)

A first substrate having a sensing element;
A second substrate that is formed with a recess surrounding the detection element and is bonded to the first substrate;
The first substrate is
A first electrode electrically connected to the detection element;
A first metal layer stacked on a surface of the first substrate facing the second substrate;
The second substrate is
A second electrode joined to the first electrode;
A second metal layer facing the first metal layer and joined to the first metal layer,
The surface of the first electrode and the surface of the first metal layer are located on substantially the same plane,
The surface of the second electrode and the surface of the second metal layer are also located on substantially the same plane,
The second substrate further includes an annular protrusion that is located between the second electrode and the second metal layer and electrically insulates the second electrode and the second metal layer. A featured detection device. The detection device according to claim 1,
The width of the annular protrusion narrows continuously or stepwise as it goes toward the tip surface of the annular protrusion. The detection device according to claim 2,
At least one of the inner peripheral surface or the outer peripheral surface of the annular protrusion is a tapered inclined surface. The detection device according to claim 1,
The second substrate further includes an auxiliary protrusion,
The detection device according to claim 1, wherein a tip surface of the auxiliary projection includes a lower portion than a tip surface of the annular projection. A first element having a detection element; a first electrode electrically connected to the detection element; and a first metal layer having a surface substantially coplanar with the surface of the first electrode. A first step of preparing one substrate;
Located between the second electrode, the second metal layer having a surface that is substantially coplanar with the surface of the second electrode, and between the second electrode and the second metal layer A second step of preparing a second substrate having an annular protrusion and a concave portion having a lens portion on the bottom surface;
The second electrode, the second electrode, the surface of the second electrode, the surface of the second metal layer, and the height from the tip surface of the annular protrusion to the lens portion are within a predetermined range. A third step of collectively scraping the metal layer and the annular protrusion;
A fourth step of bonding the first and second metal layers and bonding the first and second electrodes in a state where the detection element and the lens portion are opposed to each other. A method for manufacturing a featured detection device. A method of manufacturing a detection device according to claim 5,
The width of the annular protrusion is narrowed continuously or stepwise toward the tip surface of the annular protrusion,
The third step determines a shaving amount of the second electrode, the second metal layer, and the annular protrusion based on a width of a tip surface of the annular protrusion exposed from the second metal layer. The manufacturing method of the detection apparatus characterized by the above-mentioned. A method of manufacturing a detection device according to claim 5,
The second substrate further includes an auxiliary protrusion,
The tip surface of the auxiliary projection includes a lower portion than the tip of the annular projection,
In the third step, the shaving amounts of the second electrode, the second metal layer, and the annular protrusion are determined based on the area of the tip surface of the auxiliary protrusion exposed from the second metal layer. The manufacturing method of the detection apparatus characterized by the above-mentioned.

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