JP2007299961A - Semiconductor device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the frequency of the generation of damage to a sensor chip in a resin sealing process by forming a proper angle of inclination to a sealing resin inclined to the sensor chip. <P>SOLUTION: A semiconductor device has a semiconductor element 1 necessary to be exposed to the outside, and a protective layer 8 for the semiconductor element 1. The angle of the inclination 5 of an opening 3 formed at the protective layer 8 is formed at an angle from 5° to 45° to the surface of the semiconductor element 1. Consequently, a hold-down piece 18 for forming the opening can suppress stress applied to the semiconductor element 1 when the protective layer 8 is formed, and the frequency can be reduced in the generation of damages to the semiconductor element 1. The shape of the exposed section of the semiconductor element 1 can be brought near easily to an object to be measured, and the semiconductor device can be obtained having the proper size of the opening 3 set to the size of the semiconductor element 1 fitted in the opening 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a package shape and structure of a semiconductor device that requires an opening for exposing a sensor chip and the like.

  A conventional example will be described with reference to the structure of a resin-sealed package for a fingerprint sensor currently on the market. As a specific example, a touch type fingerprint authentication sensor AES3400 (WQFP48-1414: AES3400 Authen Tec Inc.) manufactured by Authentec will be described as an example.

  5 and 6 show a sealed package having an opening using the above-described conventional QFP (Quad Flat Package), and a sensor chip 101, that is, a fingerprint recognition area, is provided on the upper surface of the package in order to authenticate a fingerprint. It is exposed. In the fingerprint authentication device, the sensor chip 101 has almost such an opening 103.

  FIG. 7 shows the concept of resin sealing. The sensor chip 101 is sandwiched between mold dies 116 and 117 while being mounted on the lead frame 107.

  In order to seal the sensor chip 101 with resin, in this state, the opening forming pressing piece 118 is brought into close contact with the sensor surface, and the resin is injected. A sensor tactile-capable opening window 103 is formed by closely attaching the opening forming presser piece 118 to the sensor surface. The opening forming presser piece 118 is generally made of metal, and is formed by an opening forming presser piece tapered surface 119 and a surface that touches the sensor for ease of processing and easy mold separation after sealing. The corner opening forming presser taper taper angle 120 is 45 °. Note that the opening forming pressing piece taper angle 120 becomes the opening window inclination angle 104 of the sensor chip 101 package itself.

  However, when the conventional opening forming presser taper taper angle 120 is used, there is a problem that the sensor chip is frequently damaged when the mounting height of the sensor chip 101 varies. This is because the sensor opening window inclination angle 105 of the sensor chip 101 to be exposed is about 45 °, and therefore, when the semiconductor chip is sealed with resin, the opening forming presser piece 118 is brought into close contact with the sensor surface. This is because the stress applied to the edge of the portion 103 acts greatly on the sensor surface. Furthermore, when the mounting height of the sensor chip 101 is mounted at a high position, the sensor surface of the sensor chip 101 is strongly pressed against the corner portion (edge) of the holding piece, and the stress applied to the sensor surface by the edge is further increased. The sensor chip 101 was frequently damaged.

  In the case where the small sensor chip 101 is sealed with resin, in a state where the size of the opening 103 provided for the sensor chip is minimized, when the sensor opening window inclination angle 105 is set to 45 °, the non-contact region of the fingertip 115 with respect to the sensor 113 occurs (FIG. 8). For this reason, the dimension of the opening 103 must be large enough to ensure that the fingertip enters.

  Therefore, in order to perform fingerprint authentication, there is a limit to reducing the size of the opening. Since the opening 103 cannot be reduced, it is difficult to reduce the size of the sensor chip itself. Moreover, this means that the sensor chip size itself cannot be reduced, and it has been difficult to reduce material costs.

  In addition, when the sensor opening window inclination angle 105 is 45 °, the boundary between the upper surface of the package and the sensor opening window inclination surface 104 when the user brings the fingertip 115 into contact with the opening 103 for fingerprint authentication. There was a horny feel, and it became a cause of discomfort such as roughness and catching.

  The present invention has been made in view of the above-described problems. The object of the present invention is to make the size of the sensor chip 101 and the opening 103 minimum with respect to the upper surface of the sensor chip 101 while enabling fingerprint authentication. By providing an appropriate inclination angle to the inclined sealing resin portion 108, stress distribution to the edge of the opening on the sensor surface is achieved in the step of resin-sealing the semiconductor chip, and the sensor chip in the resin sealing step The purpose is to reduce the frequency of breakage.

  In order to solve the above problems, a semiconductor device according to the present invention includes a semiconductor element that needs to be exposed to the outside in a semiconductor device that requires an opening, and a protective layer for the semiconductor element. The inclination angle of the opening provided in the layer is formed at an angle larger than 5 ° and smaller than 45 ° with respect to the surface of the semiconductor element.

  According to said structure, the inclination | tilt angle of the opening part provided in the said protective layer is formed at an angle larger than 5 degrees and smaller than 45 degrees with respect to the surface of the said semiconductor element. For this reason, the semiconductor device in which the portion where the semiconductor element is exposed can be easily brought close to the measurement object and the size of the opening set with respect to the size of the semiconductor element installed in the opening is realized. There is an effect.

  The semiconductor device according to the present invention may be a fingerprint authentication device. The semiconductor devices may be connected by wire bonding.

  If the semiconductor device is a fingerprint authentication device, a fingerprint authentication device that matches the shape of the fingertip can be realized. Moreover, even if it connects by wire bonding, the magnitude | size of an opening part and the magnitude | size of a semiconductor element can be produced appropriately.

  In the semiconductor device according to the present invention, it is preferable that a symbol for recognizing a sensor portion of the semiconductor element is described in a portion where the semiconductor element is exposed to the outside.

  The description of the symbol for recognizing the sensor part has an effect that the position of the sensor in the opening can be easily identified.

  Furthermore, the semiconductor element used in the semiconductor device according to the present invention may be a land grid array or a ball grid array. Further, it may be a land grid array composed of a flex-rigid substrate or a ball grid array composed of a flex-rigid substrate.

  In addition, in order to solve the above-described problem, the method of manufacturing a semiconductor device according to the present invention sandwiches the semiconductor element with the mold in a state where the mold to be molded is closely attached to the surface of the semiconductor element, and puts the resin into the mold. A method of manufacturing a semiconductor device in which a protective layer is formed by injecting into a mold, wherein the protective layer has an opening that exposes a surface of the semiconductor element, and an opening provided in the protective layer The opening forming portion of the mold has a tapered surface so that the inclination angle is formed at an angle larger than 5 ° and smaller than 45 ° with respect to the surface of the semiconductor element.

  According to said structure, since the inclination-angle of the opening part provided in the said protective layer is formed at an angle larger than 5 degrees and smaller than 45 degrees with respect to the surface of the said semiconductor element, formation of the said protective layer Sometimes, the stress applied to the semiconductor element by the opening forming pressing piece can be suppressed, and the frequency of breakage of the semiconductor element can be reduced.

  As described above, a semiconductor device according to the present invention includes a semiconductor element that needs to be exposed to the outside in a semiconductor device that requires an opening, and a protective layer for the semiconductor element, and is provided in the protective layer. Since the inclination angle of the formed opening is 5 ° or more and 45 ° or less with respect to the surface of the semiconductor element, the portion where the semiconductor element is exposed can be easily brought close to the measurement object, and the opening There is an effect of realizing a semiconductor device in which the size of the opening set with respect to the size of the semiconductor element installed in the portion is appropriate.

  In addition, as described above, in the method for manufacturing a semiconductor device according to the present invention, the semiconductor element is sandwiched between the molds in a state where the mold to be molded is closely attached to the surface of the semiconductor element, and the resin is put into the mold. A method of manufacturing a semiconductor device in which a protective layer is formed by implantation, wherein the protective layer has an opening that exposes a surface of the semiconductor element, and an inclination angle of the opening provided in the protective layer is Since the opening forming portion of the mold has a tapered surface so as to be formed at an angle larger than 5 ° and smaller than 45 ° with respect to the surface of the semiconductor element, the opening is formed when the protective layer is formed. The stress exerted on the semiconductor element by the pressing piece can be suppressed, and the frequency of occurrence of breakage of the semiconductor element can be reduced.

  An embodiment of the present invention will be described below with reference to FIGS.

  FIG. 2 is a top view of an LGA (Land Grid Array) package formed according to the present invention, and FIG. 3 is a cross-sectional view of the LGA package. On the upper surface of the package, an area including the sensor chip effective element area 2 is exposed in order to authenticate the fingerprint. The sensor chip effective element region display line 6 is also formed on the same surface. The sensor chip 1 is formed on the frame substrate 7 and connected to the package mounting connection terminal 10 on the substrate by a gold wire 9.

  The sealing resin 8 is formed on the sensor chip effective element region 2 side of the sensor chip 1, and at that time, the sensor tactile feasible opening window 3 is opened in a region including the sensor chip effective element region 2. A sensor opening window inclined surface 4 is attached to the boundary between the sensor tactile-capable opening window 3 and the sealing resin 8. In the present invention, the sensor opening window inclined angle 5 formed by the sensor opening window inclined surface 4 and the sensor chip 1 is formed at an angle larger than 5 ° and smaller than 45 °.

  Here, a method of forming the LGA package will be described with reference to FIG. FIG. 1 shows the concept of resin sealing. In this method, the sensor chip 1 is sandwiched between the mold dies 16 and 17 while being mounted on the frame substrate 7 and fixed.

  At this time, the opening forming pressing piece 18 is inserted between the sensor surface and the mold 16, the opening forming pressing piece 18 is brought into close contact with the sensor surface, and the resin is injected. The opening forming presser piece 18 is inclined such that the angle formed by the opening forming presser piece taper surface 19 and the surface touching the sensor forms an opening forming presser piece taper angle 20. The sensor tactile possible opening window 3 is formed by the above process at an angle within the above angle range. After the resin is fixed, the molds 16 and 17 and the opening forming presser piece 18 are removed to complete the formation of the LGA package.

  Conventionally, the sensor opening window inclination angle 5 formed by the opening forming presser piece 18 is generally 45 °. However, in the method of the present invention, the angle is larger than 5 ° and smaller than 45 °. Is formed. It is possible to easily form the opening forming presser piece 18 at an angle specified in the present application in the current working technique. When forming the LGA package using the opening forming presser piece 18, the opening forming unit is formed. Since the sensor opening window inclination angle 5 formed by the holding piece 18 becomes gentler than when the conventional opening forming holding piece 18 is used, the edge portion can be formed cleanly.

  Further, in the above description, the sensor opening window inclination angle 5 is formed by the opening forming presser piece 18, but it is also possible to form the mold die 16 having the shape of the opening forming presser piece 18.

  FIG. 4 is a diagram showing a positional relationship between the LGA package and a cross-sectional view when fingerprint authentication is performed using the LGA package formed according to the present invention.

  The sensor chip 1 is sealed with a sealing resin 8 in order to fix the sensor chip 1 itself and protect the gold wire 9 and the like. Therefore, the sensor chip effective element region 2 on the sensor chip 1 is fixed at a position recessed with respect to the sealing resin 8. In FIG. 4, it is assumed that the size of the sensor chip 1 is smaller than the fingertip 15. In this configuration, in order to perform fingerprint authentication, it is necessary to bring the fingertip 15 into contact with the sensor chip effective element region 2, and it is necessary to press the fingertip 15 into the recess. In the case of the LGA package formed by the conventional opening forming presser piece 18, the sensor opening window inclination angle 5 is 45 °, so that the sealing resin 8 is abruptly compared with the shape of the fingertip 15. Since it is formed so as to rise from the chip 1, when the user touches the fingertip 15 with the opening 3 for fingerprint authentication, there is a crisp feel at the boundary between the package upper surface and the sensor opening window inclined surface 4. , Roughness and catching, causing discomfort.

  Further, in the case of the LGA package formed by the conventional opening forming presser piece 18, the shape of the recess in the portion where the sensor chip 1 is exposed is significantly different from the shape of the fingertip 15, so that the user's finger is the sensor. There was a large area (fingertip non-contact area 13) that did not touch.

  In general, when the sensor opening window inclination angle 5 is a deep angle (in the case of an angle of 45 ° or more), the shape of the recess in the portion where the sensor chip 1 is exposed is greatly different from the shape of the surface of the fingertip 15. It becomes. In this case, the boundary between the upper surface of the package and the inclined surface 4 of the sensor opening window has an angular feel, which not only causes a sense of incongruity such as roughness and catching, but also allows the finger to touch the sensor because the non-contact area 13 is widened. The opening window 3 must open wide with respect to the sensor chip 1.

  In addition, when the sensor opening window inclination angle 5 is a very shallow angle (in the case of an angle of 5 ° or less), the sensor chip 1 is installed in a recess formed gently from the upper surface of the package. In addition, when the user presses the fingertip 15, it is expected that not only the feeling of strangeness such as catching is small, but also the fingertip non-contact area 13 is reduced.

  However, since the sensor chip 1 needs to fix the gold wire 9 for contacting the package mounting connection terminal 10 on the substrate and the sensor chip 1 itself, the thickness sealed with the sealing resin 8 is somewhat. It is necessary to form thicker than the above. Therefore, if the sensor opening window inclination angle 5 is set very shallow, the sensor opening window inclination surface 4 needs to be formed large in order to give the sealing resin 8 a thickness. As a result, there arises a problem that the size of the LGA package becomes large.

  In the LGA package formed by the opening forming presser piece 18 of this embodiment, the sensor opening window inclination angle 5 is larger than 5 ° and smaller than 45 °, so that the sensor chip 1 is exposed. It is easy to match the shape of the dent of the part to the shape of the fingertip 15, and the size of the opening 3 set for the sensor chip 1 installed in the opening 3 can be made relatively small. Further, the inclination angle of the sensor opening window inclination angle 5 can be set so that the size of the LGA package does not become too large.

  As an example, the material for the opening forming presser piece 18 is made of metal, and the opening forming presser piece taper 19 is 30 ° with respect to the surface where the opening forming presser piece 18 and the sensor chip 1 are in close contact with each other. An example in which the pressing portion taper angle 20 for opening formation is set so as to be inclined and actually manufactured will be described. In this case, the sensor opening window inclination angle 5 of the sensor tactile-capable opening window 3 is also 30 °.

  When actually manufactured, when the opening window inclination angle 5 is the conventional shape (45 °), sensor chip breakage of about 5% occurred, whereas the opening forming pressing piece 18 described above. As a result, an LGA package was manufactured with an opening window inclination angle 5 of 30 °, and among the 2500 packages prepared, the number of sensor chip breakage was 0.

  Further, when the opening forming pressure piece taper angle 20 is set so that the opening window inclination angle 5 is 30 °, the stress applied to the edge of the opening forming pressure piece 18 causes the angle to be 45 °. It is expected to be reduced compared with the setting. When a trial calculation was actually performed, it was estimated that the stress applied to the edge portion of the sensor chip 1 at the edge portion was reduced to about 1/3.

  A sensor chip effective element region display line 6 for centering the sensor chip opening 3 and the sensor chip effective region 2 may be formed inside the opening 3 on the upper surface of the package. By forming the sensor chip effective element area display line 6, it is possible to easily determine that the inside of the area display line 6 is the sensor effective area 2. Those found above can be easily excluded as defective products. Further, the sensor chip effective element region display line 6 can also be used for position adjustment of the molds 16 and 17 and the frame substrate 7 during the molding process in FIG. Moreover, you may make it judge that it is a part which a user presses a finger | toe.

  In this embodiment, the LGA package has been described as an example. However, the present invention is not limited to the form of the package, and the package shape of the semiconductor device that requires the opening 3 for exposing the sensor chip 1 and the like. And can be applied to structures. As another example, FIG. 9 shows an embodiment in a BGA (Ball Grid Array) package, and FIGS. 10 and 11 show an embodiment in a flex / rigid type package.

  As described above, according to the present invention, the sensor effective area can be efficiently contacted even when the size of the opening and the sensor chip is minimized. Can do. Moreover, the frequency of occurrence of sensor chip breakage in the molding process during the manufacturing process is reduced, which has the effect of reducing the defective rate during production.

  In addition, by providing effective area display marks on components such as sensor chips that are exposed to the aperture, it is possible to easily shift the position of components such as sensors from the aperture simply by checking the actual mark that was placed during the appearance inspection of the aperture. Since it is possible to detect all of them even in appearance inspection, it leads to quality improvement. Furthermore, the stability of the resin sealing process and the chip mounting process can be confirmed at the same time.

  Furthermore, by optimizing the sensor opening inclination angle, it is possible to simultaneously eliminate the feeling of roughness and catching when a finger is directly in contact with the opening.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The present invention can be applied to the package shape and structure of a semiconductor device that requires an opening for exposing a sensor chip or the like.

It is sectional drawing which shows the process of resin-sealing a semiconductor chip in the manufacturing process of the fingerprint authentication apparatus of this invention. It is a top view of the fingerprint authentication device of the present invention. It is sectional drawing of the fingerprint authentication apparatus of this invention. FIG. 3 is a cross-sectional view showing a contact area between a fingertip and a sensor chip effective element area 2 in the fingerprint authentication device of the present invention. It is a top view of the conventional fingerprint authentication apparatus. It is sectional drawing of the conventional fingerprint authentication apparatus. FIG. 6 is a cross-sectional view showing a contact area between a fingertip and a sensor chip effective element area 102 in a conventional fingerprint authentication device. It is sectional drawing which shows the process of resin-sealing a semiconductor chip in the manufacturing process of the conventional fingerprint authentication apparatus. It is sectional drawing of the fingerprint authentication apparatus (BGA type) of this invention. It is sectional drawing of the fingerprint authentication apparatus (flex rigid type) of this invention. It is sectional drawing of the fingerprint authentication apparatus (BGA and a flex-rigid shared type) of this invention.

Explanation of symbols

1 Sensor chip (semiconductor element)
2 Sensor chip effective element area 3 Sensor tactile opening window (opening)
4 Sensor opening window inclined surface 5 Sensor opening window inclination angle (inclination angle of opening)
7 Frame substrate (chip mounting, wiring equipment)
8 Sealing resin (protective layer)
13 Fingertip non-contact area 16 Mold (top)
17 Mold (bottom)
18 Opening Forming Pressing Block 19 Opening Forming Pressing Block Tapered Surface 20 Opening Forming Pressing Block Taper Angle 21 Ball Terminal for Package Mounting Connection 22 Connector for Package Connection 23 Flex / Rigid Board

Claims (9)

In a semiconductor device having, in a protective layer, an opening that exposes the surface of a semiconductor element.
The semiconductor device is characterized in that an inclination angle of the opening provided in the protective layer is formed at an angle larger than 5 ° and smaller than 45 ° with respect to the surface of the semiconductor element.   The semiconductor device according to claim 1, wherein the semiconductor device is a fingerprint authentication device.   The semiconductor device according to claim 1, wherein the semiconductor elements are connected by wire bonding. In the opening where the semiconductor element is exposed to the outside,
The semiconductor device according to claim 1, wherein a symbol for recognizing a sensor part of the semiconductor element is described.   The semiconductor device according to claim 1, wherein the semiconductor element is a land grid array.   The semiconductor device according to claim 1, wherein the semiconductor element is a ball grid array.   5. The semiconductor device according to claim 1, wherein the semiconductor element is a land grid array including a flex-rigid substrate.   5. The semiconductor device according to claim 1, wherein the semiconductor element is a ball grid array formed of a flex-rigid substrate. A method of manufacturing a semiconductor device having, in a protective layer, an opening that exposes a surface of a semiconductor element,
In the manufacturing method of the semiconductor device, the semiconductor element is sandwiched between the molds in a state where the mold to be molded is adhered to the surface of the semiconductor element, the resin is injected into the mold, and the protective layer is formed. ,
The inclination angle of the opening provided in the protective layer is
A method of manufacturing a semiconductor device, wherein an opening forming portion of the mold has a tapered surface so as to be formed at an angle larger than 5 ° and smaller than 45 ° with respect to the surface of the semiconductor element.

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