JP2012112728A - Optical sensor device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical sensor device that may be downsized by increasing an aspect ratio of an opening of a lead frame and a method for manufacturing the same.SOLUTION: An optical sensor device comprises: an IR element 10 for detecting infrared; an optical filter 20 formed on the IR element 10; a first lead frame 31 having a penetrating first opening; a second lead frame 36 having a penetrating second opening; and a mold resin 50 covering the IR element 10 and the optical filter 20. The first lead frame 31 is disposed on the second lead frame 36 with the first opening and the second opening overlapping in a plan view, the IR element 10 and the optical filter 20 are disposed in an area where the first opening and the second opening overlap in a plan view (namely, in an opening 51) and a light receiving surface 21 of the optical filter 20 is exposed from the mold resin.

Description

  The present invention relates to an optical sensor device for detecting light such as infrared rays and a method for manufacturing the same.

  As this type of prior art, for example, there is one disclosed in Patent Document 1. As shown in FIG. 2, this document discloses an infrared sensor having a structure in which a sensor element with an optical filter that transmits only infrared rays is covered with a resin except for its light receiving surface. The sensor element is a quantum photodiode that generates a photovoltaic effect by infrared rays. The optical filter has a function of transmitting only infrared rays having a specific wavelength.

JP 2010-133946 A

By the way, as disclosed in Patent Document 1, when an optical filter is attached to a sensor element and these are arranged in an opening through which the lead frame penetrates to form one package, the opening of the lead frame has a sensor element. A depth greater than the sum of the thickness, the thickness of the optical filter, and the loop height of the wire made of Au or the like is required. That is, as shown in FIG. 17, the thickness of the lead frame 90 (= the depth of the opening 91) is T1, the thickness T2 of the sensor element 95, the thickness T3 of the optical filter 96, the sensor element 95, When the loop height of the wire 97 for electrically connecting the lead frame 90 is T4, T1 needs to satisfy the following expression (1).
T1> T2 + T3 + T4 (1)

However, when the lead frame 90 is made thick, not only the depth T1 of the opening 91 but also the width W of the opening 91 is widened, which causes a problem that the infrared sensor cannot be reduced in size.
Specifically, the opening 91 through which the lead frame 90 penetrates as shown in FIG. 17 can be formed, for example, by etching the lead frame 90 from the front surface 90a side and the back surface 90b side. This etching is isotropic wet etching, and etching in the horizontal direction (X direction, Y direction) proceeds simultaneously with the etching of the lead frame 90 in the depth direction (Z direction). For this reason, the larger the thickness of the lead frame 90, the larger the width W of the opening 91 formed.

As another method for forming such an opening 91, a method of punching the lead frame 90 using a mold may be considered. In this method, the width W is larger than the thickness T1 of the lead frame 90. Small openings cannot be formed.
Therefore, the present invention has been made in view of such circumstances, and it is possible to increase the aspect ratio of the opening portion of the lead frame, and to realize the downsizing of the optical sensor device and It aims at providing the manufacturing method.

  In order to solve the above-described problem, an optical sensor device according to an aspect of the present invention includes an optical sensor element that detects light, an optical filter that is stacked on the optical sensor element, and a first opening that penetrates the optical sensor element. A first lead frame; a second lead frame having a penetrating second opening; and a sealing member that covers the optical sensor element and the optical filter. A region in which the first lead frame is disposed, the first opening and the second opening overlap in a plan view, and the first opening and the second opening overlap in a plan view Further, the optical sensor element and the optical filter are arranged, and a light receiving surface of the optical filter is exposed from the sealing member.

  With such a configuration, one lead frame is configured by a combination of the first lead frame and the second lead frame. The width of the opening of this one lead frame (that is, the region where the first opening and the second opening overlap) is the first opening (or the second opening). The depth of the first opening and the second opening is the sum of the depths of the first opening and the second opening. Thereby, an opening having a narrow width and a deep width (that is, a large aspect ratio) is realized. The optical sensor device can be miniaturized. As the “sealing member”, for example, a mold resin 50 described later corresponds. In addition, the “region where the first opening and the second opening overlap in plan view” corresponds to, for example, openings 51, 61, and 62 described later.

  Further, in the above-described optical sensor device, the optical sensor element includes a first optical sensor element and a second optical sensor element, and the optical filter is a first layer stacked on the first optical sensor element. And the second optical filter having characteristics different from those of the first optical filter and stacked on the second photosensor element, the first opening and the second opening In the plan view includes a first region and a second region having a position different from that of the first region, and the first photosensor element and the first optical filter include the first region. The second photosensor element and the second optical filter may be disposed in the region, and the second optical sensor element and the second optical filter may be disposed in the second region.

  Here, examples of the “characteristic” include a light transmittance characteristic depending on the wavelength. For example, the first optical filter has a function of selectively transmitting only light in the first wavelength range (that is, high transmittance) as its characteristics. The second optical filter has a function of selectively transmitting only light in a second wavelength range different from the first wavelength range as its characteristics. With such a method, for example, the intensity of light incident from the outside based on the electrical signal output from the first photosensor element and the electrical signal output from the second photosensor element. Can be specified for each wavelength range. Therefore, for example, it can be used very suitably for a human sensor or a flame sensor. The “first region” corresponds to, for example, an opening 61 described later. As the “second region”, for example, an opening 62 described later corresponds.

  Further, in the above optical sensor device, the first lead frame is disposed on the first surface of the second lead frame, and is opposite to the first surface of the second lead frame. The second surface may be entirely covered with the sealing member. With this configuration, the second surface of the second lead frame included in the package is entirely covered with the resin member, and the first and second lead frames ( In the following, these are also simply referred to as a lead frame). For this reason, for example, even when a droplet or the like adheres to the light receiving surface side, the droplet does not touch the lead frame, and the optical filter and the lead frame are prevented from being short-circuited via the droplet. be able to. In addition, since the lead frame is not exposed on the light receiving surface side of the optical filter, for example, it is possible to prevent the user from misidentifying the lead frame as the light receiving surface of the optical filter. The “first surface” corresponds to, for example, surfaces 66a and 86a described later. The “second surface” corresponds to, for example, back surfaces 66b and 86b described later.

  The method of manufacturing an optical sensor device according to another aspect of the present invention includes a first opening portion that the first lead frame has and a second opening portion that the second lead frame has. A step of disposing the first lead frame on the first surface of the second lead frame so as to overlap in plan view; and a second side opposite to the first surface of the second lead frame. The optical sensor element and the optical sensor element are laminated in a region in which the first opening and the second opening overlap in a plan view with the step of attaching the adhesive surface of the adhesive tape to the surface Disposing the optical filter, attaching the light receiving surface of the optical filter to the adhesive surface of the adhesive tape, covering the optical sensor element and the optical filter with a sealing member, Sealing member and second lead Removing the adhesive tape from the frame, characterized in that it comprises a step of forming a package by cutting and the sealing member and the first lead frame and the second lead frame.

  With such a method, one lead frame can be configured by combining the first lead frame and the second lead frame. The width of the opening of this one lead frame (that is, the region where the first opening and the second opening overlap in plan view) is the same as the width of the first opening or the second opening. While keeping the same size as each width, the depth can be made the sum of the depths of the first opening and the second opening. Accordingly, an opening having a narrow width and a large depth (that is, a large aspect ratio) can be realized, so that the photosensor device can be downsized.

  In the method of manufacturing the optical sensor device, the optical sensor element includes a first optical sensor element and a second optical sensor element, and the optical filter is stacked on the first optical sensor element. A first optical filter and a second optical filter having characteristics different from those of the first optical filter and stacked on the second photosensor element, wherein the first opening and the second optical filter The region where the opening overlaps in plan view includes a first region and a second region having a position different from that of the first region, and the step of arranging the photosensor element and the optical filter includes the step of Disposing one optical sensor element and the first optical filter in the first region, and attaching a light receiving surface of the first optical filter to the adhesive surface of the adhesive tape; Second light sensor element and second light Placing the filter in the second region and pasting the light receiving surface of the second optical filter to the adhesive surface of the adhesive tape, and forming the package, The sealing member and the first lead so that the first photosensor element, the first optical filter, the second photosensor element, and the second optical filter are included in the same package. The frame and the second lead frame may be cut.

  If it is such a method, the optical sensor apparatus which can each detect the light which injects from the external field for every several wavelength range can be provided, for example. This optical sensor device specifies the intensity of incident light for each wavelength range based on the electrical signal output from the first optical sensor element and the electrical signal output from the second optical sensor element. It becomes possible to do. Therefore, for example, it is possible to provide an optical sensor device that is extremely suitable for a human sensor or a flame sensor.

  In the method of manufacturing the optical sensor device, the second lead frame includes a first part that is an inner side of the package and a second part that is an outer side of the package. The portion of the first portion is smaller in thickness than the second portion, and when the first surface is directed upward and the second surface is directed downward, the second portion of the first portion The surface may be located above the second surface of the second part. With such a method, the second surface of the second lead frame included in the package can be entirely covered with the sealing member. Therefore, it is possible to provide an optical sensor device in which the lead frame is not exposed on the light receiving surface side of the optical filter.

  According to the present invention, the aspect ratio of the opening portion of the lead frame can be increased, and the downsizing of the optical sensor device can be realized.

The figure which shows the structural example of IR sensor apparatus 100 which concerns on 1st Embodiment. The figure which shows an example of the external appearance of IR sensor apparatus. FIG. 3 is a diagram illustrating a configuration example of an IR element 10. FIG. 3 is a diagram illustrating a configuration example of a first lead frame 31 according to the first embodiment. FIG. 3 is a diagram illustrating a configuration example of a second lead frame 36 according to the first embodiment. The figure which shows the manufacturing method of IR sensor apparatus. The figure which shows an example of the temporary fixing method of the 1st, 2nd lead frames 31 and 36. FIG. The figure which shows the structural example of IR sensor apparatus 200 grade | etc., Which concerns on 2nd Embodiment. The figure which shows an example of the external appearance of IR sensor apparatus. The figure which shows the manufacturing method of IR sensor apparatus. The figure which shows the structural example of IR sensor apparatus 300 which concerns on 3rd Embodiment. The figure which shows an example of the external appearance of IR sensor apparatus 300. FIG. The figure which shows the structural example of the 1st lead frame 71 which concerns on 3rd Embodiment. The figure which shows the structural example of the 2nd lead frame 76 which concerns on 3rd Embodiment. The figure which shows the structural example of IR sensor apparatus 400 grade | etc., Which concerns on 4th Embodiment. The figure which shows an example of the external appearance of IR sensor apparatus. The figure for demonstrating a subject.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. Note that, in each drawing described below, parts having the same configuration are denoted by the same reference numerals, and repeated description thereof may be omitted.
(1) First Embodiment (1.1) Schematic Configuration of IR Sensor Device FIGS. 1A and 1B are a plan view showing a configuration example of an IR sensor device 100 according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line A1-A′1 of the plan view. In FIG. 1A, the illustration of the mold resin is omitted in order to avoid complication of the drawing. In FIG. 1A, a hatched area indicates a half-etched area from the surface side (hereinafter also referred to as a half-etched area), and a gray area is not half-etched from the surface side. A region (hereinafter referred to as a non-etched region) is shown. Further, in FIG. 1B, in order to clarify the bonding state between the IR element and the lead frame, the wire on the near side or the far side of the paper surface in the cross section is also illustrated.

As shown in FIGS. 1A and 1B, this IR sensor device 100 includes an IR element 10, an optical filter 20 laminated (attached) on the light receiving surface of the IR element 10, a lead frame 30, and the like. And a wire 40 made of gold (Au) or the like for electrically connecting the IR element 10 and the lead frame 30, and a mold resin 50 covering the IR element 10 and the optical filter 20.
As shown in FIG. 1B, the lead frame 30 includes a first lead frame 31 and a second lead frame 36, which are overlapped to form one lead frame 30. The IR element 10 and the optical filter 20 are arranged in the opening 51 through which the lead frame 30 passes.

Further, as shown in FIG. 1B, in this IR sensor device 100, the light receiving surface 21 of the optical filter 20 is exposed from the mold resin 50 and is flush with the back surface 36b of the second lead frame 36. (That is, to be flush with each other).
FIG. 2 is a perspective view showing an example of the external appearance of the IR sensor device 100. As shown in FIG. 2, the shape of the package of the IR sensor device 100 is, for example, a rectangular parallelepiped. The light receiving surface 21 of the optical filter is disposed so as to be flush with the upper surface of the package (that is, the back surface 36b of the second lead frame and the surface of the mold resin 50). External light is incident on the light receiving surface 21 of the optical filter, passes through the optical filter, and reaches the light receiving surface of the IR element. Hereinafter, each element which comprises the IR sensor apparatus 100, and its manufacturing method are demonstrated in detail.

(1.2) Configuration of IR Element and Optical Filter FIGS. 3A and 3B are diagrams showing a configuration example of the IR element 10. 3A shows the surface side of the IR element 10, and FIG. 3B shows a cross section of the photoelectric conversion element 13. An IR element 10 shown in FIG. 3A is an optical sensor element that detects infrared rays, a light transmission substrate 11 that transmits light such as infrared rays, and a light receiving portion 12 formed on the surface side of the light transmission substrate 11. And comprising.

  Among these, a GaAs substrate is used as the light transmission substrate 11. In addition to the GaAs substrate, for example, a semiconductor substrate such as Si, InAs, InP, GaP, or Ge, or a substrate such as GaN, AlN, sapphire substrate, or glass substrate is used. According to such a substrate, light of a specific wavelength such as infrared light can be efficiently transmitted from the back surface 16 to the front surface of the light transmission substrate 11.

  In addition, the light receiving unit 12 includes a plurality of photoelectric conversion elements 13, a pad unit 14 for outputting an electrical signal photoelectrically converted by the photoelectric conversion element 13, and a wiring 15. Each of the photoelectric conversion elements 13 is a quantum photodiode and is connected in series by a wiring 15. As the number of connected photoelectric conversion elements 13 increases, the generated electromotive force increases, and the sensitivity as a sensor increases.

  As shown in FIG. 3B, the photoelectric conversion element 13 includes, for example, an n-type compound semiconductor layer (n layer) such as InSb containing indium (ln) and antimony (Sb) formed on the light transmission substrate 11. ) 13a, a non-doped compound semiconductor layer (π layer) 13b formed on the n layer 13a, and an AlInSb layer formed on the π layer 13b and having a larger band gap than the n layer 13a and the π layer 13b. Such a compound semiconductor layer 13c and a p-type compound semiconductor layer (p layer) 13d formed on the compound semiconductor layer 13c and doped with a p-type impurity at a high concentration are configured. Thus, the photoelectric conversion element 13 in which the n layer 13a, the π layer 13b, the compound semiconductor layer 13c having a larger band gap than the n layer 13a and the π layer 13b, and the p layer 13d are sequentially stacked has a thickness of 2000 nm. Infrared light of ˜7400 nm can be detected.

  The pad portion 14 shown in FIG. 3A is provided to output an electrical signal obtained by photoelectric conversion of the light receiving portion 12 to the IC element. The pad portion 14 includes, for example, a pair of pad electrodes 14a and 14b that are disposed apart from each other. The wiring 15 is electrically connected between one pad electrode 14a and one end of the row of the plurality of photoelectric conversion elements 13, and between the other pad electrode 14b and the other end of the row. .

  By the way, in this IR element 10, the pad portion 14 is arranged in a partial range (center portion) closer to the center of the surface of the IR element 10. A plurality of photoelectric conversion elements 13 are arranged around the pad portion 14. According to such an arrangement, there is an advantage that the light transmitting substrate 11 is not easily lost even when pressure or ultrasonic waves are applied when wire bonding is performed to the pad electrodes 14a and 14b. Further, since the light transmission substrate 11 is not easily damaged, a wire made of Au or the like can be bonded to the pad electrodes 14a and 14b with sufficient pressure or ultrasonic waves. For this reason, a wire can be reliably crimped | bonded by pad electrode 14a, 14b, and the reliability of wire bonding can be improved.

On the other hand, the optical filter 20 (see FIG. 1B) laminated on the back surface (that is, the light receiving surface) 16 of the IR element 10 selectively selects light in a desired wavelength range (that is, has high transmittance). It has a function of transmitting. For example, the optical filter 20 has a function of transmitting only infrared rays.
Alternatively, the optical filter 20 may have a function of transmitting only infrared rays in a specific wavelength range among infrared rays. For example, the optical filter 20 has an optical member and a thin film formed in a multilayer on the optical member, and has a function of not transmitting infrared rays having a long wavelength, a short wavelength, or both, and these It may have a function of transmitting only infrared rays having a specific wavelength as a result of combining the transmission functions.

The optical filter 20 may perform a function of transmitting only infrared rays having a specific wavelength, or may use a plurality of sheets depending on circumstances. In addition, as a material of the optical member, a material that transmits predetermined infrared rays such as silicon (Si), glass (SiO ₂ ), sapphire (Al ₂ O ₃ ), Ge, ZnS, ZnSe, CaF ₂ , and BaF ₂ is transmitted. The thin film materials used and deposited on this include silicon (Si), glass (SiO ₂ ), sapphire (Al ₂ O ₃ ), Ge, ZnS, TiO ₂ , MgF ₂ , SiO ₂ , ZrO ₂ , Ta ₂ O ₅ or the like is used. In addition, the dielectric multilayer filter in which dielectrics having different refractive indexes are laminated in layers on the optical member may be formed on both sides with a predetermined thickness configuration different on the front and back sides, or formed only on one side. May be. Further, for the purpose of preventing unnecessary reflection, an antireflection film may be formed on the front surface, both surfaces on the back surface, or the outermost layer on one surface.

(1.3) Configuration of Lead Frame FIGS. 4A and 4B are plan views showing a configuration example of the first lead frame 31 according to the first embodiment of the present invention. FIG. 4A shows the front surface 31 a of the first lead frame 31, and FIG. 4B shows the back surface 31 b of the first lead frame 31.
In the first lead frame 31 shown in FIGS. 4A and 4B, for example, a copper (Cu) plate is selectively etched from the front surface 31a side and the back surface 31b side by a photolithography technique. (Ni) -palladium (Pd) -gold (Au) or other plating (plating) treatment is performed.

  In FIG. 4A, the white area in the first lead frame 31 shows the first opening 32 penetrating between the front surface 31a and the back surface 31b, and the hatched area is from the front surface 31a side. A half-etched region (that is, a half-etched region) 33a is shown. A gray region indicates a region (that is, a non-etched region) 34a that is not etched by masking the surface 31a with a photoresist or the like during etching.

Similarly, in FIG. 4B, the white region in the first lead frame 31 indicates the first opening 32, and the hatched region is a half-etched region 33b that is half-etched from the back surface 31b side. Indicates. A gray region indicates a non-etched region 34b that was not etched by masking the back surface 31b with a photoresist or the like during etching.
The outer periphery of the first lead frame 31 shown in FIGS. 4A and 4B is a region (referred to as a kerf width) 35 that is cut by a dicing blade or the like in a dicing process described later.

FIGS. 5A and 5B are plan views showing a configuration example of the second lead frame 36 according to the first embodiment of the present invention. FIG. 5A shows the front surface 36 a of the second lead frame 36, and FIG. 5B shows the back surface 36 b of the second lead frame 36.
Like the first lead frame 31 shown in FIGS. 4A and 4B, the second lead frame 36 shown in FIGS. 5A and 5B is made of, for example, a Cu plate by photolithography technology. Thus, the surface 36a and the back surface 36b are selectively etched from each side and plated with Ni—Pd—Au or the like.

  In FIG. 5A, the white area in the second lead frame 36 indicates the second opening 37 that penetrates between the front surface 36a and the back surface 36b, and the gray area indicates that the front surface 36a is a photoresist during etching. A non-etched region 39a that has not been etched is shown by being masked with the like. In FIG. 5A, there is no half-etched region. The surface 36a of the lead frame 36 is flat.

  Similarly, in FIG. 5B, the white region in the second lead frame 36 indicates the second opening 37, and the gray region is etched by masking the back surface 36b with a photoresist or the like during etching. The non-etched region 39b that was not present is shown. A hatched region indicates a half-etched region 38a that is half-etched from the back surface 36b side. The outer periphery of the second lead frame 36 shown in FIGS. 5A and 5B has a kerf width 35 that is cut by a dicing blade or the like in a dicing process described later.

  As can be seen by comparing FIGS. 4A and 4B with FIGS. 5A and 5B, the first opening 32 of the first lead frame 31 and the second lead frame 36 The second openings 37 are formed so that the shapes in plan view (that is, the planar shape) are the same and the lengths in plan view (ie, the length in the vertical and horizontal directions) are also the same. Therefore, as shown in FIGS. 1A and 1B, when the first lead frame 31 and the second lead frame 36 are overlapped, the two openings 32 and 37 are overlapped to form one continuous line. The opening 51 is configured. The shape and size (that is, vertical and horizontal dimensions) of the opening 51 in plan view are the same as those of the first and second openings 32 and 37, respectively. The depth of the opening 51 is the sum of the depths of the first and second openings 32 and 37.

Next, a method for manufacturing the IR sensor device 100 using the first and second lead frames 31 and 36 will be described.
(1.4) IR Sensor Device Manufacturing Method FIGS. 6A to 6G are process diagrams showing a manufacturing method of the IR sensor device 100 according to the first embodiment of the present invention. In addition, each cross section in this process drawing respond | corresponds to the cut surface by the A1-A'1 line | wire of IR sensor apparatus 100 shown, for example to Fig.1 (a).

  As shown in FIG. 6A, first, a first lead frame 31 ′ and a second lead frame 36 ′ are prepared. Here, the first lead frame 31 shown in FIGS. 4A and 4B is used as one unit pattern, and the unit patterns are arranged so as to be continuously arranged in the vertical direction and the horizontal direction in plan view. A lead frame 31 'is prepared. Similarly, the second lead frame 36 shown in FIGS. 5A and 5B is used as one unit pattern, and the unit patterns are arranged so as to be continuously arranged in the vertical direction and the horizontal direction in plan view. A lead frame 36 'is prepared.

Next, the adhesive tape 41 is affixed to the back surface 36b of the second lead frame 36 '. By sticking the adhesive tape 41 on the back surface 36 b side of the second lead frame 36 ′, the adhesive layer of the adhesive tape 41 is exposed on the bottom surface of the second opening 37.
As the adhesive tape 41, a resin tape having adhesiveness and heat resistance is used. About adhesiveness, the one where the paste thickness of the adhesion layer is thinner is preferable. Moreover, about heat resistance, it is required to endure the temperature of about 150 to 200 degreeC. As such an adhesive tape 41, for example, a polyimide tape can be used. The polyimide tape has heat resistance that can withstand about 280 ° C. Such a polyimide tape having high heat resistance can withstand high heat applied during subsequent molding or wire bonding. In addition to the polyimide tape, the following tape may be used as the adhesive tape 41.

-Polyester tape Heat-resistant temperature, about 130 ° C (however, the heat-resistant temperature reaches about 200 ° C depending on use conditions).
・ Teflon (registered trademark) tape Heat-resistant temperature: about 180 ℃
・ PPS (polyphenylene sulfide) Heat-resistant temperature: about 160 ℃
・ Glass cloth heat resistant temperature: about 200 ℃
・ Nomek Paper Heat-resistant temperature: about 150-200 ℃
In addition, aramid and crepe paper can be used as the adhesive tape 41.

  Next, the first lead frame 31 ′ is disposed on the surface 36 a of the second lead frame 36 ′. Here, the front surface 36a of the second lead frame 36 'and the back surface 31b of the first lead frame 31' face each other, and in this state, the first lead is such that the opening 32 is directly above the opening 37. The frame 31 'and the second lead frame 36' are aligned. Then, as shown in FIG. 6B, the first lead frame 31 ′ is arranged and fixed on the surface 36a of the second lead frame 36 ′ in this aligned state. As a result, a lead frame 30 'is formed.

  Here, it is not necessary to bond the first lead frame 31 ′ and the second lead frame 36 ′ with an adhesive or the like. It is sufficient to temporarily fix the first lead frame 31 ′ and the second lead frame 36 ′ so that they are not relatively displaced. The reason is that the first lead frame 31 ′ and the second lead frame 36 ′ are fixed by the mold resin 50 in the resin sealing step described later. As a temporary fixing method, for example, there are the following methods.

  That is, as shown in FIG. 7, through holes 55 and 56 are provided in the outer periphery of the first lead frame 31 'and the outer periphery of the second lead frame 36', respectively. By aligning 31 ′ and the second lead frame 36 ′, these through holes 55 and 56 overlap each other in plan view. Two or more such through holes 55 and 56 are provided in each of the first lead frame 31 ′ and the second lead frame 36 ′. Here, the first lead frame 31 ′ and the second lead frame 36 ′ are connected by fitting the pins 63 into the through holes 55 and 56 that overlap each other at a plurality of locations (for example, two locations). It can be temporarily fixed so as not to be displaced. Further, after the alignment, the four corners may be arc-welded, or only the four corners may be bonded with an adhesive.

  Next, as shown in FIG. 6C, the IR element 10 and the optical filter 20 are disposed in the opening 51 of the lead frame 30 ′. Here, the light receiving surface 21 of the optical filter 20 is pasted on the adhesive tape 41 surface, which is the bottom surface of the opening 51. Note that a protective film (not shown) may be formed in advance on the light receiving surface 21 of the optical filter 20 at the time of attachment. As the protective film, for example, a photoresist can be used. Such a protective film can be formed, for example, before dicing the optical member that is the base material of the optical filter 20.

Next, as shown in FIG. 6D, the IR element 10 and the lead frame 30 'are electrically connected. Here, as shown in FIG. 1, the pad electrodes 14a and 14b of the IR element 10 and the bonding terminal portion 42 of the lead frame 30 ′ are connected by a wire 40 made of Au or the like.
The IR element 10 and the lead frame 30 ′ are connected by extending a wire from the bonding terminal portion 42 of the lead frame 30 ′ toward the pad electrodes 14 a and 14 b of the IR element 10 (that is, viewed from the IR element 10). And reverse bonding). That is, the 1st bond accompanied with the formation of the ball is performed on the bonding terminal portion 42 of the lead frame 30 ′, and the 2nd bond is performed on the pad electrodes 14 a and 14 b of the IR element 10. With such a method, since the bonding terminal portion 42 of the lead frame 30 ′ is lower than the pad electrodes 14 a and 14 b of the IR element 10, the height of the wire after bonding can be lowered. it can.

  Next, as shown in FIG. 6E, the upper mold 47 is disposed on the front surface side of the lead frame 30 ′, and the lower mold 48 is disposed on the back surface side of the lead frame 30 ′. Then, the lead frame 30 ′ is sandwiched between the upper mold 47 and the lower mold 48, and the mold resin 50 is injected from the side into the space sandwiched between the upper mold 47 and the lower mold 48 and filled. Thereby, the IR element 10, the optical filter 20, and the wire 40 are resin-sealed.

  As the mold resin 50, for example, an epoxy resin can be used. Further, in this resin sealing step, the upper die 47 and the non-etched region on the surface 31a side of the first lead frame 31 ′ are in contact with each other without any gap, and the lower die 48 and the lead frame 30 ′ are in contact with each other. The mold resin 50 is supplied from the side of the space formed by the overlapping of both molds in a state where the non-etched region on the back surface 36b side and the adhesive tape 41 attached to the optical filter 20 are in contact with each other without a gap. For this reason, after resin sealing, the non-etched region of the first lead frame 31 ′, the non-etched region of the second lead frame 36 ′, and the optical filter 20 are exposed from the mold resin 50.

Next, as shown in FIG. 6F, the adhesive tape is removed from the back side of the lead frame 30 '. After the adhesive tape is removed, post-cure and wet blasting are performed, and when a protective film (not shown) is formed on the light receiving surface 21 of the optical filter 20, the protective film is removed.
Thereafter, as shown in FIG. 6G, the mold resin 50 and the lead frame 30 ′ are diced by a dicing apparatus, and the kerf width 35 is cut. As a result, the mold resin 50 and the lead frame 30 ′ are separated and packaged into individual products, and the IR sensor device 100 shown in FIGS. 1A and 1B and FIG. 2 is completed.

  As shown in FIGS. 1A and 1B, the first lead frame 31 has a plurality of terminal portions. These terminal portions are formed integrally with the bonding terminal portion 42 covered with the mold resin 50 and the bonding terminal portion 42, and a part thereof is exposed from the mold resin 50. Terminal portion 43. When incorporating the IR sensor device 100 into various devices, the external wiring board connecting terminal portion 43 is electrically connected to a terminal portion of a wiring board such as an interposer, for example. Thereby, the IR sensor device 100 can be mounted on the wiring board without blocking the light receiving surface 21 of the optical filter 20.

  As described above, according to the first embodiment of the present invention, one lead frame 30 can be configured by combining the first lead frame 31 and the second lead frame 36. The width of the opening 51 of the lead frame 30 (that is, the region where the first opening 32 and the second opening 37 overlap in plan view) is the first and second openings 32 and 37. The depth can be made the sum of the depths of the first and second openings 32 and 37 while keeping the same size as each of the first and second openings 32 and 37. As a result, a narrow and deep opening (that is, a large aspect ratio) can be realized, and the IR sensor device 100 can be downsized.

  Furthermore, the first embodiment of the present invention has various effects other than the above. That is, according to the first embodiment of the present invention, resin sealing is performed with the light receiving surface 21 of the optical filter 20 attached to the adhesive tape 41, and then the adhesive tape 41 is removed. Thereby, a window for allowing light to enter the light receiving surface 21 of the optical filter 20 can be formed without etching the mold resin 50. In this method, it is not necessary to etch the mold resin 50 in order to form a window for introducing light, and an etching process and a photolithography process associated therewith are not required. Can be suppressed. In addition, since it is not necessary to cause etching damage to the light receiving surface 21 of the optical filter 20, it is possible to prevent a deterioration in performance related to light reception such as light transmission.

(2) Second Embodiment In the first embodiment described above, for example, as illustrated in FIG. 2, the case where the back surface of the second lead frame is exposed on the top surface of the package has been described. However, in the present invention, it is not essential that the back surface of the second lead frame is exposed on the top surface of the package. In the second embodiment, this point will be described.

8A and 8B are a cross-sectional view showing a configuration example of the IR sensor device 200 according to the second embodiment of the present invention and a plan view showing a configuration example of the second lead frame 66. FIG.
The difference between the second lead frame 66 shown in FIGS. 8A and 8B and the second lead frame 36 described in the first embodiment is the arrangement of the half-etched region and the non-etched region on the back surface. Is a different point.

  Specifically, on the back surface 66b (that is, the second surface) of the second lead frame 66, only the half-etched region 38b exists in the region surrounded by the kerf width 35, and the non-etched region 39b does not exist. . The non-etched region 39b exists only in a region overlapping with the kerf width 35. Note that the surface 66a (that is, the first surface) of the second lead frame 66 is the same as the surface 36a of the second lead frame 36 described in the first embodiment (see, for example, FIG. 5A). The same.

  In other words, the second lead frame 66 has a first portion that is inside the package (that is, surrounded by the kerf width 35) and a second portion that is outside the package. The first portion of the second lead frame 66 is smaller in thickness than the second portion. As shown in FIG. 8A, when the front surface 66a of the second lead frame 66 is directed upward and the back surface 66b is directed downward, the back surface 66b of the first part is the second part. It is located above the back surface 66b.

  With such a configuration, as shown in FIG. 8A, the back surface 66b of the second lead frame 66 is entirely covered with the mold resin 50 inside the package. For this reason, as shown in FIG. 9, the lead frame is not exposed on the upper surface of the package of the IR sensor device 200. Only the light receiving surface 21 of the optical filter is exposed from the mold resin 50 on the upper surface of the package. Next, a method for manufacturing the IR sensor device 200 shown in FIGS. 8A and 9 will be described.

FIGS. 10A to 10G are process diagrams showing a method for manufacturing the IR sensor device 200 according to the second embodiment of the present invention. The manufacturing method of the IR sensor device 200 is performed in the same procedure as the manufacturing method described in the first embodiment.
That is, as shown in FIG. 10A, first, a first lead frame 31 ′ and a second lead frame 66 ′ are prepared. Here, the second lead frame 66 described with reference to FIG. 8A is used as one unit pattern, and the unit patterns are arranged so as to be continuously arranged in the vertical direction and the horizontal direction in plan view. A lead frame 66 'is prepared. Next, the adhesive tape 41 is affixed to the back surface 36b of the second lead frame 66 ′.

Next, as shown in FIG. 10B, the first lead frame 31 'is disposed on the surface 36a of the second lead frame 66'. Here, alignment and fixing are performed in the same manner as in the first embodiment. As a result, a lead frame 30 'is formed.
Next, as shown in FIG. 10C, the IR element 10 and the optical filter 20 are arranged in the opening 51 of the lead frame 30 ′. Then, as shown in FIG. 10D, the IR element 10 and the lead frame 30 ′ are electrically connected by a wire 40.

Next, as shown in FIG. 10 (e), the lead frame 30 ′ is sandwiched between the upper mold 47 and the lower mold 48, and the mold resin is inserted into the space between the upper mold 47 and the lower mold 48. Inject 50 and fill. Thereby, the IR element 10 and the wire 40 are resin-sealed.
Next, as shown in FIG. 10F, the adhesive tape is removed from the back side of the lead frame 30 '. After the adhesive tape is removed, post-cure and wet blasting are performed, and when a protective film (not shown) is formed on the light receiving surface 21 of the optical filter 20, the protective film is removed.

Thereafter, as shown in FIG. 10G, the mold resin 50 and the lead frame 30 ′ are diced by a dicing apparatus, and the kerf width 35 is cut. As a result, the mold resin 50 and the lead frame 30 'are separated into individual products and packaged, and the IR sensor device 200 shown in FIGS. 8A and 9 is completed.
As described above, according to the second embodiment of the present invention, the back surface 36 b of the second lead frame 66 remaining inside the package can be entirely covered with the mold resin 50. Therefore, it is possible to provide the IR sensor device 200 in which the lead frame 30 is not exposed at all on the light receiving surface 21 side (that is, the upper surface side of the package).

  According to the IR sensor device 200, even when a droplet or the like adheres to the upper surface side of the package, the droplet does not touch the lead frame 30, and the optical filter 20 and the lead frame 30 are connected via the droplet. Can be prevented from short-circuiting. Further, since the lead frame 30 is not exposed at all on the upper surface of the package, for example, it is possible to prevent the user from misidentifying the lead frame 30 as the light receiving surface 21 of the optical filter 20.

(3) Third Embodiment In the first and second embodiments described above, the case where one IR element is arranged in one package has been described. However, the present invention is not limited to this. In the present invention, two or more IR elements may be arranged in one package. In the third embodiment, this point will be described.

  FIGS. 11A and 11B are a plan view showing a configuration example of an IR sensor device 300 according to the third embodiment of the present invention, and a cross-sectional view taken along line A11-A′11. . In FIG. 11A, illustration of the mold resin is omitted to avoid complication of the drawing. In FIG. 11A, the hatched area indicates a half-etched area that is half-etched from the surface side, and the gray area indicates a non-etched area that is not half-etched. Further, in FIG. 11B, in order to clarify the state of bonding between the IR element and the lead frame, the wire on the near side or the far side of the paper surface in the cross-sectional view is also illustrated.

  As shown in FIGS. 11A and 11B, the IR sensor device 300 includes, for example, a first IR element 10a and a first optical filter 20a stacked on the light receiving surface of the first IR element 10a. And a second IR element 10b and a second optical filter b stacked on the light receiving surface of the second IR element 10b. In addition, the lead frame 70 is provided with a through opening 61 for arranging the first IR element 10a and the first optical filter 20a, and the second IR element 10b and the second optical filter 20b. A through-opening 62 is provided for the purpose.

  As shown in FIG. 11B, the lead frame 70 includes a first lead frame 71 and a second lead frame 76, which constitute one lead frame 70. As shown in FIG. 1B, in the IR sensor device 300, the light receiving surface 21a of the first optical filter 20a and the light receiving surface 21b of the second optical filter 20b are exposed from the mold resin 50, respectively. The light receiving surfaces 21a and 21b are arranged to be flush with the back surface 76b of the second lead frame 76 (that is, to be flush with each other).

  FIG. 12 is a perspective view showing an example of the external appearance of the IR sensor device 300. As shown in FIG. 12, the shape of the package of the IR sensor device 300 is, for example, a rectangular parallelepiped. The light receiving surface 21a of the first optical filter and the light receiving surface 21b of the second optical filter are respectively the upper surface of the package (that is, the back surface 76b of the second lead frame 76 and the surface of the mold resin 50). They are arranged to be flush with each other. External light is incident on the light receiving surfaces 21a and 21b, and reaches the light receiving surface of the IR element through the optical filter.

  By the way, in the third embodiment, the first optical filter 20a and the second optical filter 20b have different characteristics. For example, the first optical filter 20a selectively transmits infrared rays in the first wavelength range, and the second optical filter 20b selectively transmits infrared rays in the second wavelength range. As an example, the first wavelength range is a long wavelength, and the second wavelength range is a short wavelength. On the other hand, the first IR element 10a and the second IR element 10b are, for example, the same type of sensor element, and the configuration and function thereof are the same as those of the IR element 10 described in the first embodiment. Next, the configuration of the lead frame 70 used in the IR sensor device 300 will be described.

FIGS. 13A and 13B are plan views showing a configuration example of the first lead frame 71 according to the third embodiment of the present invention. FIG. 13A shows the front surface 71 a of the first lead frame 71, and FIG. 13B shows the back surface 71 b of the first lead frame 71.
In FIG. 13A, the white region in the first lead frame 71 indicates the through-opening portions 82 and 83, and the hatched region indicates the half-etched region 73a that is half-etched from the surface 71a side. . A gray region indicates a non-etched region 74a that is not etched from the surface 71a side. Similarly, in FIG. 13B, the white area in the first lead frame 71 shows the openings 82 and 83, and the hatched area shows the half-etched area 73b half-etched from the back surface 71b side. Show. Moreover, the gray area | region shows the non-etching area | region 74b which is not etched from the back surface 71b side.

  The first lead frame 71 shown in FIGS. 13A and 13B differs from the first lead frame 31 described in the first embodiment in that these are arranged according to the number of IR sensor elements. This is a point in which a plurality of through-opening portions are prepared. Other points are the same as those of the first lead frame 31. The outer periphery of the first lead frame 71 has a kerf width 75 that is cut in the dicing process.

14A and 14B are plan views showing a configuration example of the second lead frame 76 according to the third embodiment of the present invention. 14A shows the front surface 76a side of the second lead frame 76, and FIG. 14B shows the back surface 76b side of the second lead frame 76.
In FIG. 14A, the white region in the second lead frame 76 indicates the openings 84 and 85, and the gray region indicates the non-etched region 79a that is not etched from the surface 76a side. In FIG. 14A, there is no half-etched region. The surface 76a of the lead frame 76 is flat.

Similarly, in FIG. 14B, the white region in the second lead frame 76 indicates the openings 84 and 85, and the gray region indicates the non-etched region 79b that is not etched from the back surface 76b side. A hatched region indicates a half-etched region 78b that is half-etched from the back surface 76b side.
The second lead frame 76 shown in FIGS. 14A and 14B is different from the second lead frame 36 described in the first embodiment in that these are arranged according to the number of IR sensor elements. This is a point in which a plurality of through-opening portions are prepared. The other points are the same as those of the second lead frame 36. The outer periphery of the second lead frame 76 has a kerf width 75 that is cut in the dicing process.

  As can be seen by comparing FIGS. 13A and 13B with FIGS. 14A and 14B, the opening 82 of the first lead frame 71 and the opening 84 of the second lead frame 76. Are formed so that their planar shapes are identical to each other, and their longitudinal and lateral lengths are also identical to each other. The opening 83 of the first lead frame 71 and the opening 85 of the second lead frame 76 are also formed so that the planar shape is the same and the length and width are the same.

Then, as shown in FIG. 1B, the first lead frame 71 and the second lead frame 76 are overlapped to overlap the first opening 61 and the opening 83. , 85 and the second opening 62, respectively.
According to the third embodiment of the present invention, similarly to the first embodiment, by combining the first lead frame 71 and the second lead frame 76, the first and second openings having a high aspect ratio. 83 and 85 can be realized. For this reason, the IR sensor device 300 can be reduced in size.

  Further, the IR sensor device 300 can detect infrared rays incident from the outside world for each different wavelength range. Based on the electrical signal output from the first IR element 10a and the electrical signal output from the second IR element 10b, the intensity of the incident light is changed for each wavelength range (for example, for each long wavelength, short wavelength). For each wavelength). Therefore, for example, it can be used very suitably for a human sensor or a flame sensor.

(4) Fourth Embodiment In the third embodiment described above, for example, as shown in FIG. 12, the case where the back surface of the second lead frame is exposed on the top surface of the package has been described. However, in the present invention, it is not essential that the back surface of the second lead frame is exposed on the top surface of the package. That is, you may apply said 2nd Embodiment to 3rd Embodiment. In the fourth embodiment, this point will be described.

FIGS. 15A and 15B are a cross-sectional view showing a configuration example of an IR sensor device 400 according to the fourth embodiment of the present invention and a plan view showing a configuration example of the second lead frame 86.
The difference between the second lead frame 86 shown in FIGS. 15A and 15B and the second lead frame 76 described in the third embodiment is the arrangement of the half-etched region and the non-etched region on the back surface. Is a different point.

  Specifically, on the back surface 86b (ie, the second surface) of the second lead frame 86, only the half-etched region 78b exists in the region surrounded by the kerf width 75, and the non-etched region 79b does not exist. . The non-etching region 79b exists only in a region overlapping with the kerf width 75. Note that the surface 86a (that is, the first surface) of the second lead frame 86 is the same as the surface 76a of the second lead frame 76 described in the third embodiment (for example, see FIG. 14A). The same.

  In other words, the second lead frame 86 has a first portion that is inside the package (that is, surrounded by the kerf width 75), and a second portion that is outside the package. The first portion of the second lead frame 86 is smaller in thickness than the second portion. Further, as shown in FIG. 15A, when the front surface 86a of the second lead frame 86 is directed upward and the back surface 86b is directed downward, the back surface 86b of the first part is the second part. It is located above the back surface 86b.

  With such a configuration, as shown in FIG. 15A, the back surface 86b of the second lead frame 86 is entirely covered with the mold resin 50 inside the package. Therefore, as shown in FIG. 16, the lead frame is not exposed on the upper surface of the package of the IR sensor device 400. Only the light receiving surfaces 21 a and 21 b of the optical filter are exposed from the mold resin 50 on the upper surface of the package. According to this 4th Embodiment, there can exist an effect similar to 2nd Embodiment and 3rd Embodiment.

(5) Other Embodiments In the first embodiment described above, for example, as shown in FIG. 2A, a pair of pads is provided at the center of the surface of the IR element 10 as the pad section 14 of the IR element 10. Although the structure in which the electrodes 14a and 14b are arranged is shown, this is merely an example. In the present invention, the pad portion 14 of the IR element 10 may be composed of, for example, three or more pad electrodes that are spaced apart from each other at the center of the surface of the IR element 10. Even with such a configuration, the IR element and the lead frame can be electrically connected, and an electrical signal can be output from the IR element.

  Furthermore, in each of the above embodiments, an IR element capable of detecting infrared rays of 2000 nm to 7400 nm is illustrated as an example of the optical sensor element. However, in the present invention, the optical sensor element is not limited to this. In the present invention, the optical sensor element may be, for example, an element that detects only ultraviolet rays, or may be an element that detects both ultraviolet rays and infrared rays.

For example, in the photoelectric conversion element 13 in which an n layer, a π layer, a compound semiconductor layer having a larger band gap than the n layer and the π layer, and a p layer are sequentially stacked on a light transmitting substrate, n If other materials such as AlN, InGaP, InGaAsP, and InAsSb are used for the layer instead of InSb, it is possible to create an optical sensor element that can detect ultraviolet rays with a wavelength of about 250 nm to infrared rays with a wavelength of about 12 μm. is there. In such a case, an optical sensor device that can detect ultraviolet rays to infrared rays can be provided.
In this case, the optical filter may also have a function of transmitting only ultraviolet rays, for example, or may transmit both ultraviolet rays and infrared rays. The wavelength range in which the optical filter can be transmitted can be arbitrarily set according to the wavelength range in which the optical sensor element can be detected.

10, 10a, 10b IR element 11 Light transmitting substrate 12 Light receiving part 13 Photoelectric conversion element 13a n layer 13b π layer 13c compound semiconductor layer 13d p layer 14 pad part 14a pad electrode 14b pad electrode 15 wiring 16 back surface of IR element 10 (light receiving) surface)
20, 20a, 20b Optical filters 21, 21a, 21b Light receiving surfaces 30, 70 (consisting of optical filters) Lead frames 31, 71 First lead frames 31a, 36a, 66a, 71a, 76a, 86a Front surface 31b, 36b, 66b, 71b, 76b, 86b Back surface 32, 37, 51, 61, 62, 82, 83, 84, 85 Opening 33a, 33b, 38a, 38b, 73a, 73b, 78a, 78b Half etching Regions 34a, 34b, 39a, 39b, 74a, 74b, 79a, 79b Non-etched regions 35, 75 Calf widths 36, 66, 76, 86 Second lead frame 40 Wire 41 Adhesive tape 42 Terminal portion 43 for bonding External wiring substrate Connecting terminal portion 47 Upper die 48 Lower die 50 Mold resin 5 Through holes 63 pins 100, 200, 300, 400 IR sensor device

Claims (6)

An optical sensor element for detecting light;
An optical filter laminated on the optical sensor element;
A first lead frame having a first opening therethrough;
A second lead frame having a second opening therethrough;
A sealing member that covers the optical sensor element and the optical filter,
The first lead frame is disposed on the second lead frame, and the first opening and the second opening overlap in plan view,
The optical sensor element and the optical filter are arranged in a region where the first opening and the second opening overlap in plan view,
An optical sensor device, wherein a light receiving surface of the optical filter is exposed from the sealing member. The photosensor element includes a first photosensor element and a second photosensor element,
The optical filter includes a first optical filter stacked on the first photosensor element, and a second optical filter having characteristics different from those of the first optical filter and stacked on the second photosensor element. Including
The region where the first opening and the second opening overlap in plan view includes a first region and a second region having a position different from that of the first region,
The first optical sensor element and the first optical filter are disposed in the first region;
The optical sensor device according to claim 1, wherein the second optical sensor element and the second optical filter are disposed in the second region. The first lead frame is disposed on a first surface of the second lead frame;
3. The optical sensor device according to claim 1, wherein the second surface opposite to the first surface of the second lead frame is entirely covered with the sealing member. 4. The first surface of the second lead frame so that the first opening portion that the first lead frame has and the second opening portion that the second lead frame has are overlapped with each other in plan view. Disposing the first lead frame thereon;
Attaching a surface having adhesiveness of an adhesive tape to a second surface opposite to the first surface of the second lead frame;
An optical sensor element and an optical filter laminated on the optical sensor element are disposed in a region where the first opening part and the second opening part overlap in plan view, and the light receiving surface of the optical filter is attached to the adhesive layer. A step of applying to the adhesive surface of the tape;
Covering the optical sensor element and the optical filter with a sealing member;
Removing the adhesive tape from the sealing member and the second lead frame;
And a step of cutting the sealing member, the first lead frame, and the second lead frame to form a package. The photosensor element includes a first photosensor element and a second photosensor element,
The optical filter includes a first optical filter stacked on the first photosensor element, and a second optical filter having characteristics different from those of the first optical filter and stacked on the second photosensor element. Including
The region where the first opening and the second opening overlap in plan view includes a first region and a second region having a position different from that of the first region,
The step of arranging the optical sensor element and the optical filter includes:
Disposing the first optical sensor element and the first optical filter in the first region, and attaching a light receiving surface of the first optical filter to the adhesive surface of the adhesive tape; ,
Placing the second photosensor element and the second optical filter in the second region, and affixing the light receiving surface of the second optical filter to the adhesive surface of the adhesive tape; Including,
In the step of forming the package,
The sealing member and the first optical sensor element, the first optical filter, the second optical sensor element, and the second optical filter are included in the same package. The method for manufacturing an optical sensor device according to claim 4, wherein the lead frame and the second lead frame are cut. The second lead frame is
A first portion that is an inner side of the package and a second portion that is an outer side of the package;
The first portion is thinner than the second portion, and
When the first surface is directed upward and the second surface is directed downward, the second surface of the first portion is above the second surface of the second portion. The method of manufacturing an optical sensor device according to claim 4, wherein the optical sensor device is located at a position.

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