Optical sensor package

Abstract

The invention relates to an optical sensor package. An optical sensor module includes a glass cover that protects a sensor die and a perimeter frame for securing the glass cover. The perimeter frame may hold the glass cover in a position suspended above the sensor die and spaced apart from the sensor die by an air gap. Epoxy seals the glass cover between the perimeter frame and the package. The addition of the perimeter frame creates a longer path length for moisture and gas permeation, preventing moisture from reaching the sensor die, while allowing light to enter the sensor die.

Description

Technical Field

[0001] The present invention relates to assembling and packaging semiconductor device modules, semiconductor device assemblies, and semiconductor devices. More particularly, the present invention relates to semiconductor device modules including molded optical sensors. Background Art

[0002] Semiconductor device assemblies, such as assemblies including optical sensors such as image sensors (such as silicon photomultipliers (SiPMs) and SiPM arrays), can be implemented using one or more semiconductor dies, one or more substrates, and electrical interconnects such as wire bonds, conductive spacers, and conductive clips. Known semiconductor device assemblies may have structural integrity issues that may prevent use in some electronic applications. Summary of the invention

[0003] In some aspects, the technology described herein relates to a device comprising: a leadframe; a semiconductor die coupled to the leadframe; an optically transparent cover separated from the semiconductor die by a gap; a package surrounding the semiconductor die, the package being configured to support a perimeter of the optically transparent cover and coupled to the perimeter of the optically transparent cover by a sealant; and a perimeter frame disposed on top of at least a portion of the perimeter of the optically transparent cover so that the optically transparent cover is fixedly coupled (e.g., held in place) between the perimeter frame and the package.

[0004] In some aspects, the technology described herein relates to a method comprising: forming a lead frame having a substrate and leads; attaching a semiconductor die to the substrate; coupling the semiconductor die to the leads using wire bonds; forming an optical package around the lead frame, the semiconductor die, and the wire bonds; covering the semiconductor die with a glass cover; disposing a perimeter frame over the glass cover; and securing the glass cover and the perimeter frame to the optical package.

[0005] In some aspects, the technology described herein relates to a tube die package, which includes: a lead frame; a glass cover, which is suspended above the lead frame; a peripheral frame, which is above the glass cover; and an encapsulation material, which is configured to conform to the lead frame, the glass cover and the peripheral frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1A is a cross-sectional view of an optical sensor module equipped with a perimeter frame according to a specific implementation of the present disclosure.

[0007] Figure 1B According to the specific implementation of the present disclosure Figure 1A A plan view of the optical sensor shown.

[0008] Figure 2 , Figure 3 and Figure 4A is a cross-sectional view of an optical sensor module equipped with different perimeter frame designs according to specific implementations of the present disclosure.

[0009] Figure 4B According to the specific implementation of the present disclosure Figure 4A Side elevation view of the perimeter frame shown.

[0010] Figure 5 The present invention is a method for manufacturing a Figure 1A , Figure 1B , Figure 2 , Figure 3 , Figure 4A and Figure 4B A flow chart of a method of an optical sensor module is shown.

[0011] When the following detailed description is read together with the accompanying drawings, the various aspects of the present disclosure are best understood therefrom. It should be noted that, according to the conventions in the industry, various features are not necessarily drawn to scale. For the clarity of discussion, the sizes of various features may be increased or reduced arbitrarily. In the accompanying drawings, similar reference symbols may indicate similar and / or similar parts (elements, structures, etc.) in different views. The accompanying drawings generally illustrate various specific implementations discussed in the present disclosure by way of example and not limitation. The reference symbols shown in one accompanying drawing may not be repeated for the same and / or similar elements in the related views. The reference symbols repeated in multiple accompanying drawings may not be specifically discussed with respect to each of the figures in these figures, but are provided for the context between the related views. In addition, not all similar elements in the accompanying drawings are specifically referenced with reference symbols when multiple instances of the element are shown. DETAILED DESCRIPTION

[0012] Current implementations of semiconductor device assemblies may have certain disadvantages. These semiconductor device assemblies, such as, for example, optical sensor modules formed around optical sensor dies, such as, for example, image sensors such as CMOS image sensors, may include a silicon microlens array. For example, current implementations may be assembled into a chip package that includes a transparent cover, such as a glass cover, located above the optical sensor die. The transparent cover covers and protects the optical sensor while transmitting light to the central active area of ​​the image sensor die. The transparent cover may also provide an air cavity above the microlens array at the silicon surface. One failure mode that may occur in such devices is a moisture ingress-related failure, in which the transparent cover may separate from the chip package. The moisture resistance of the device depends on the adhesive epoxy layer between the transparent cover and the chip package. If the "glass to package" bond is not strong enough, the transparent cover may separate from the chip package during a thermal event, such as due to warping of the package or due to expansion of air trapped in the cavity.

[0013] The present disclosure relates to implementations of semiconductor device assemblies that include optical sensors in which the package has mechanical fixing features in addition to the adhesive epoxy layer to improve the robustness of the glass-to-package bond. The package can be formed earlier using a pre-molding process, rather than by injection molding at the end of the manufacturing process, so that the package itself can be used as a structural support during assembly of the optical sensor module. Multiple adhesive layers can then be used to fix and conform other structural components to the package.

[0014] In some implementations, a molding compound (e.g., an epoxy molding compound) may be used as an encapsulant to protect the components of the semiconductor device assembly described herein. An encapsulated semiconductor device assembly or chip assembly may be referred to as a packaged device or a semiconductor device module. Semiconductor device assemblies including optical sensors or light sensors may be used in many image processing applications, including cameras, smart phones, video surveillance equipment, infrared imaging systems, automotive systems including light detection and ranging (LiDAR), and industrial applications.

[0015] Figure 1A is a cross-sectional view of an optical sensor module 100 equipped with a fixing frame 110 according to some specific implementations of the present disclosure, and Figure 1B In addition to the fixing frame 110 , the optical sensor module 100 further includes a package 102 , a sensor die 104 , a cavity 105 , a transparent cover 106 and an adhesive layer 108 .

[0016] Package 102 is composed of an encapsulant (e.g., a molding compound). In some implementations, package 102 can be a pre-molded phenolic epoxy package, a ceramic carrier package, or any open cavity optoelectronic sensor package. In some implementations, package 102 can be manufactured using a film assisted mold. Figure 1A In the example of FIG. 1 , the top of the package 102 has a substantially vertical inner sidewall profile. In some implementations, the lower portion of the inner sidewall 112 of the package 102 extends below the perimeter of the transparent cover 106 to provide support for the transparent cover 106. In some implementations, the package 102 can have an outer dimension in the range of about 3 mm to about 25 mm. In some implementations, the package 102 can have a height in the range of about 1.5 mm to about 6.0 mm.

[0017] In some implementations, the sensor die 104 may be a semiconductor die that includes an optical sensor, such as a CMOS image sensor, i.e., an image sensor that includes a metal oxide semiconductor field effect transistor (MOSFET) and related integrated circuit components. In some implementations, the sensor die 104 may include an optical sensor in the form of a silicon photomultiplier tube or a silicon photomultiplier tube array. In some implementations, the sensor die 104 may include a microlens array. The sensor die 104 may be attached to (e.g., disposed on, mounted on, coupled to, or in direct contact with) an upper surface of the package 102. The active region may be located in a central region of the sensor die 104. The active region may be a region formed on an epitaxial layer of the sensor die 104. The active region of the sensor die 104 may include an electronic component configured with a photosensitive element for sensing light (e.g., reflected light from a target or an external object), which will form a digital image of the target. In some implementations, the sensor within the active region on the sensor die 104 may have a thickness in the range of about 1 mm to about 20 mm.

[0018] In some implementations, the sensor die 104 may be formed on a substrate that includes a ceramic material, a glass material, a semiconductor material, an organic material, a resin material, a laminate, or a printed circuit board. In some implementations, the substrate may include a portion of a semiconductor wafer in which integrated circuit components (such as transistors) and interconnects (e.g., metallization layers) are formed. For example, the substrate may be made of silicon, silicon carbide (SiC), or a III-V semiconductor material such as gallium arsenide (GaAs), indium phosphide (InP), or may include the above. In some implementations, the substrate may be a glass substrate or a sapphire substrate.

[0019] The cavity 105 is formed around the sensor die 104. In some implementations, the cavity 105 is bounded above by the transparent cover 106 and laterally by the package 102. In some implementations, the cavity 105 can be an air cavity, or the cavity 105 can be filled with an inert gas, such as nitrogen (N2) gas. The cavity 105 can include (e.g., provide) a gap 107 (e.g., a spacer) between the sensor die 104 and the transparent cover 106. Similar to the cavity 105, the gap 107 can be an air gap, or a gap filled with an inert gas such as nitrogen (N2) gas. The gap 107 can have a thickness (e.g., vertical extent) in the range of about 0.02 mm to about 1.3 mm.

[0020] Light detected by the sensor die 104 may be received by the transparent cover 106, which may provide environmental protection for at least the active area of ​​the sensor die 104. The transparent cover 106 may be made of glass or another optically transparent material such as a polymer material having suitable optical properties, such as, for example, PMMA, acrylic, a transparent form of polyvinyl chloride (PVC), or the like. The transparent cover 106 is protected by the encapsulation 102, which surrounds the sidewalls 109 of the transparent cover 106. In the example of FIG. 1 , the vertical sidewalls 109 of the transparent cover 106 conform to the vertical portions of the inner sidewalls 112 of the encapsulation 102. The encapsulation 102 assists in preventing mechanical damage to the transparent cover 106. The encapsulation 102 may provide edge support for the transparent cover 106 to maintain the vertical position of the transparent cover 106 suspended above the sensor die 104, so that the air cavity 105 surrounds both the sides and the top of the sensor die 104, thereby maintaining the gap 107 separating the transparent cover 106 from the sensor die 104.

[0021] In some implementations, the adhesive layer 108 may be an adhesive film. In some implementations, the adhesive layer 108 may be a sealant, such as an epoxy resin, a thermoplastic epoxy resin, and / or an organic-based sealant. The adhesive layer 108 fills the space between the inner sidewall 112 of the package 102 and the fixed frame 110. The adhesive layer 108 also fills the space between the inner sidewall 112 of the package 102 and the transparent cover 106. In addition, the adhesive layer 108 fills the space between the fixed frame 110 and the periphery of the transparent cover 106. The adhesive layer 108 thus provides an extended moisture penetration path, which prevents moisture from reaching the sensor die 104 (e.g., the image sensor die) while allowing light to reach the image sensor.

[0022] In some implementations, adhesive layer 108 includes different parts, for example, a first adhesive layer 108a, a second adhesive layer 108b, and a third adhesive layer 108c, which can be applied by different methods at different times during the manufacturing process. First adhesive layer 108a can be characterized as being located on a horizontal surface of a package (e.g., package 102); second adhesive layer 108b can be characterized as being located on a peripheral surface of transparent cover 106. Third adhesive layer 108c can be characterized as filling a space, such as a space between inner sidewall 112 of package 102 and sidewall 109 of transparent cover 106 and a space between inner sidewall 112 of package 102 and fixing frame 110.

[0023] In some implementations, the fixing frame 110 and the transparent cover 106 are disposed within the recessed area of ​​the package 102. The fixing frame 110 (e.g., a perimeter frame) provides additional security for the bond between the transparent cover 106 and the package 102. The fixing frame 110 is bonded to the transparent cover 106 and to the inner sidewall 112 of the package 102. The fixing frame 110 is disposed on top of at least a portion of the perimeter of the transparent cover 106, thereby holding (e.g., locking) the transparent cover 106 in place between the fixing frame 110 and the package 102. The fixing frame 110 is positioned on the optically transparent cover so that the optically transparent cover is fixedly coupled between the perimeter frame and the package.

[0024] In some specific implementations, the fixing frame 110 is a rigid fixed peripheral feature attached to the upper side wall (e.g., vertical side wall) of the package 102 using the third adhesive layer 108c. The fixing frame 110 is also attached to at least a portion of the periphery of the upper surface of the transparent cover 106 using the second adhesive layer 108b and covers the at least a portion. The shape of the fixing frame 110 is consistent with the upper portion of the inner side wall 112, so that the fixing frame 110 has a substantially rectangular profile, as seen in the cross-sectional view. In some specific implementations, the fixing frame 110 can be made of an injection molding material such as a hardened liquid crystal polymer (LCP). In some specific implementations, the fixing frame 110 may have a size in the range of about 1 mm to about 25 mm, and a thickness in the range of about 0.2 mm to about 3.0 mm.

[0025] Figure 2 2 is a cross-sectional view of an optical sensor module 200 equipped with a package 202 and a fixing frame 210 according to some implementations of the present disclosure. The optical sensor module 200 includes a sensor die 104, an air gap 207, a transparent cover 106, and an adhesive layer 108.

[0026] like Figure 2 As shown, the optical sensor module 200 also includes several components. For the sake of clarity, Figure 1AThese elements are omitted from the cross-sectional view of the optical sensor module 100 shown. Figure 2 Further shown are leadframe 203 and wirebonds 204. In some implementations, leadframe 203 may be cut or stamped from a thin rolled sheet of metal (e.g., copper). Leadframe 203 may include a base and leads, such as contact pads 203a, disposed around the perimeter of leadframe 203. Sensor die 104 is coupled to (e.g., disposed on) the top of, above, and / or in contact with the substrate of leadframe 203. Wirebonds 204 may extend from contact pads 203a to an interconnect layer in the upper surface of sensor die 104. The interconnect layer may be a metal layer, such as a metal pad or a patterned metal layer that forms a wire interconnect. For example, the upper surface of sensor die 104 may include an interconnect layer that provides a signal path for a device below, such as a metal wire or a fiber optic connector. In some implementations, the back side of sensor die 104 may support solder balls that contact the lower surface (e.g., a metallization layer on the back side of sensor die 104). In some implementations, solder balls can be used to mount the sensor die 104 to the lead frame 203. Other methods of bonding the sensor die 104 to the lead frame 203 can be used instead of solder balls, such as direct bonding.

[0027] Wire bonds 204 provide electrical connections (e.g., data transmission paths) between circuit elements on sensor die 104 and external electronics (e.g., electronics that can process or store image information sensed by sensor die 104). Wire bonds 204 can be supported and protected by package 202, which surrounds wire bonds 204, sensor die 104, and at least a portion of the sidewalls of transparent cover 106.

[0028] In the optical sensor module 200, the package 202, the air gap 207 and the fixing frame 210 have the same Figure 1A The optical sensor modules 100 are shown in different shapes from their counterparts. Figure 2 The optical sensor module 200 is shown with Figure 1A The optical sensor module 100 shown is different in that the inner sidewall 212 of the package 202 is inclined rather than vertical, while the sidewall of the transparent cover 106 is vertical. Therefore, the distance d1 between the top of the transparent cover 106 and the inner sidewall 212 is greater than the distance d2 between the bottom of the transparent cover 106 and the inner sidewall 212. That is, the sidewall of the transparent cover 106 is not parallel to the inner sidewall 212 of the package 202. The package 202 is made of an encapsulation material, such as a pre-molded epoxy or ceramic that is consistent with the lead frame 203, the transparent cover 106 and the fixing frame 110. The shape of the fixing frame 210 is consistent with the sidewall 212, so that the fixing frame 210 has a trapezoidal profile parallel to the inclined inner sidewall 212, rather than the rectangular profile of the fixing frame 110. In addition, in Figure 2 In the example shown, the inner sidewalls 212 of the package 202 extend laterally inwardly below the transparent cover 106 to form an extended shelf that supports the transparent cover 106 and overlaps the edge of the sensor die 104 so that the package 202 completely surrounds and supports the wire bonds 204. Thus, the cavity is reduced to the space between the transparent cover 106 and the sensor die 104, for example, to the gap 207. In some implementations, the gap 207 is tapered so that the gap 207 has a trapezoidal profile defined by the inclined lower portion of the sidewalls 212. As shown in Figure 1A In the example shown, the adhesive layer 108 extends around the sides and bottom of the transparent cover 106, and around the sides and bottom of the fixed frame 210, so that the adhesive layer 108 (e.g., the third adhesive layer 108c) fills the space between the side wall 212 and the fixed frame 210, the space between the side wall 212 and the transparent cover 106, and the space between the fixed frame 210 and the transparent cover 106. In some implementations, the thickness of the adhesive layer 108 can be in the range of about 0.2 mm to about 3.0 mm.

[0029] Figure 3 2 is a cross-sectional view of an optical sensor module 300 equipped with a fixing frame 310 according to some specific implementations of the present disclosure. The optical sensor module 300 includes a package 202, a lead frame 203, contact pads 203a, wire bonds 204, a sensor die 104, an air gap 207, a transparent cover 106, an adhesive layer 108, and a fixing frame 310.

[0030] Figure 3 The optical sensor module 300 shown is Figure 2 The optical sensor module 200 shown is different in that the fixing frame 310 is different from the fixing frames 110 and 210. In the optical sensor module 300, the fixing frame 310 has Figure 1A An alternative shape to its counterpart in the optical sensor module 100 is shown. Figure 3 In the example shown, the package 202 has Figure 2 106, wherein the top of the sidewall 212 is inclined and the package 202 extends below the transparent cover 106. However, the fixing frame 310 extends outward to cover the top perimeter of the package 202, so that the fixing frame 310 has an L-shaped profile. The L-shaped profile is conformal (e.g., parallel) to the inner sidewall 212 of the package 202. The adhesive layer 108 also extends across the top surface of the package 202 to bond the fixing frame 310 to the package 202. The fixing frame 310 extending on the top of the package 102 further increases the bonding strength of the adhesive layer 108. In addition, the longer seal creates a longer path length for moisture and gas to penetrate into the air gap 207.

[0031] Figure 4A is a cross-sectional view of an optical sensor module 400 equipped with a fixing frame 410 (divided into two parts 410a and 410b) according to some implementations of the present disclosure. Figure 4B is a side elevation view of the fixing frame 410 along the inclined upper portion of the sidewall 212. The optical sensor module 400 includes a package 202, a lead frame 203, contact pads 203a, wire bonds 204, a sensor die 104, an air gap 207, a transparent cover 106, and an adhesive layer 108.

[0032] In the optical sensor module 400, the fixing frame 410 is different from Figure 3 The fixed frame 310 is shown. Figure 4A and Figure 4B In the example shown, the fixing frame 410 has an L-shaped profile, similar to the profile of the fixing frame 310. However, the fixing frame 410 is discontinuous, for example, the fixing frame 410 may be patterned to include cutouts or fixing holes 412. Figure 4A As shown in the cross-sectional view of , the fixing frame 410 appears to include two parts separated by the fixing hole 412, namely, an upper part 410a and a lower part 410b.

[0033] Figure 4B The plane in which the fixing holes are formed is shown. In some specific implementations, the fixing holes 412 can be arranged in an array, such as a linear array or a matrix. In some specific implementations, the fixing retainers 412 are rectangular in shape and are spaced apart according to a pitch p, wherein the pitch p defines the distance between the repeating features of the array. The fixing holes 412 are configured to receive (e.g., filled with) an epoxy resin, such as the adhesive layer 108. The fixing holes 412 provide a keying feature that increases the bonding strength between the fixing frame 410 and the package 202, thereby increasing the mechanical stability of the structure that fixes the position of the transparent cover 116.

[0034] As in Figure 1A , Figure 2 and Figure 3 In the previous example shown, the adhesive layer 108 extends around the sides and bottom of the transparent cover 106 and around the sides and bottom of the fixed frame 210, so that the adhesive layer 108 fills the space between the side wall 212 and the fixed frame 210, the space between the side wall 212 and the transparent cover 106, and the space between the fixed frame 210 and the transparent cover 106.

[0035] Figure 5 is a flowchart showing a method 500 for manufacturing an optical sensor module 100 according to some specific implementations of the present disclosure. Figure 1A , Figure 1B , Figure 2 , Figure 3 , Figure 4A and Figure 4B In some implementations described, operations 502 to 514 of method 500 may be performed to form an optical sensor module, such as optical sensor module 100, 200, 300, or 400. The operations of method 500 may be performed in a different order, or not performed at all, depending on the particular application. It is noted that method 500 may not produce a complete optical sensor module 100. Therefore, it should be understood that additional processes may be provided before, during, or after method 500, and some of these additional processes may be briefly described herein.

[0036] At 502, according to Figure 2 In some implementations shown, method 500 includes forming a lead frame, such as lead frame 203. Lead frame 203 can be formed as a rolled copper sheet, which can be patterned or cut to provide features, such as contact pads 203a. In some implementations, lead frame 203 can have a thickness in the range of about 0.1 mm to about 0.5 mm.

[0037] At 504, method 500 includes: Figure 2 Some implementations shown attach a semiconductor die, such as an (optical) sensor die 104, to a lead frame 203. The sensor die 104 may be attached to the lead frame 203 using solder or by applying an adhesive (e.g., epoxy) or an adhesive film (such as, for example, a polyimide tape).

[0038] At 506, method 500 includes performing the following steps: Figure 2 Some implementations shown couple the semiconductor die (e.g., sensor die 104) to contact pads 203a via wire bonds 204. Wire bonds 204 may be made of aluminum, copper, gold, or any other suitable metal or metal alloy. Wire bonds 204 may be secured to contact pads 203a, for example, by soldering.

[0039] At 508, according to Figure 2 In some embodiments shown, method 500 includes forming package 202. Package 202 may be formed, for example, by injection molding, where a fluid insulating material (e.g., molding compound or ceramic) is injected into a mold so as to flow around wire bonds 204 and fill spaces between contact pads 203a and other surface features of lead frame 203. Alternatively, package 202 may be pre-molded into Figure 2 The shape shown is then attached to the lead frame 203 .

[0040] At 510, according to Figure 2In some implementations shown, the method 500 includes depositing a first adhesive layer 108a onto the package 202. Specifically, the first adhesive layer 108a can be formed on a lower horizontal surface of the package 202, on which the transparent cover 106 will rest. In some implementations, for example, for the optical sensor module 300 and the optical sensor module 400, the first adhesive layer 108a can be additionally formed on an upper horizontal surface of the package 202, on which an L-shaped fixing frame (e.g., the fixing frame 310 or the fixing frame 410) will rest. In some implementations, the first adhesive layer 108a can be an adhesive film deposited onto the horizontal surface of the package 202. In some implementations, the first adhesive layer 108a can be an epoxy resin that can be dispensed onto the horizontal surface of the package 202.

[0041] At 512, according to Figure 1A , Figure 2 , Figure 3 and Figure 4A In some implementations shown, method 500 includes covering the semiconductor die (e.g., sensor die 104) with a protective transparent cover (e.g., transparent cover 106). In some implementations, transparent cover 106 may be formed from a glass substrate (e.g., a glass wafer or a sapphire wafer) that, when patterned and cut, will form a plurality of transparent covers 106. Cutting may include a process of cutting, sawing, or scoring the glass substrate along a cutting line (e.g., along a cutting boundary) to separate square segments of the glass substrate to thereby form individual transparent covers 106. The cutting technique for the glass substrate may be similar to the cutting technique used to cut a semiconductor wafer into individual dies or chips. In some implementations, a transparent polymer substrate may replace the glass substrate. If the transparent substrate used is made of a polymer material, a different or modified segmentation technique may be employed to achieve clean cuts along the segmentation boundary. The edge of the transparent cover 106 may rest on the horizontal perimeter surface of the package 202 so as to suspend the transparent cover 106 above the sensor die 104 so that the transparent cover 106 is separated from the sensor die 104 by a gap, such as a rectangular gap 107 or a trapezoidal gap 207. The first adhesive layer 108 will be used to hold the transparent cover 106 in place until the fixing frame 210 is attached.

[0042] At 514, according to Figure 2 In some implementations shown, method 500 includes depositing a second adhesive layer 108b. The second adhesive layer 108b can be deposited on the top peripheral surface of the transparent cover 106. In some implementations, the second adhesive layer 108b can be an adhesive film. In some implementations, the second adhesive layer 108b can be an epoxy resin.

[0043] At 516, according to Figure 2In some embodiments shown, the method 500 includes attaching a fixing frame 210. In some embodiments, the fixing frame (e.g., the fixing frame 210, 310, or 410) can be formed by injection molding. The molding material can be, for example, a liquid crystal polymer. The fixing frame 210 is a rigid frame that rests on the second adhesive layer 108b and is spaced apart from the sidewalls 212 of the package 202. In some embodiments, the fixing frame 210 is a peripheral frame that surrounds the entire perimeter of the transparent cover 106. In some embodiments, the fixing frame 210 is a peripheral frame that surrounds a portion or multiple portions of the perimeter of the transparent cover 106. In some embodiments, for example, for an optical sensor module 300 that includes an L-shaped fixing frame (e.g., the fixing frame 310), the fixing frame is attached to the first adhesive layer 108a on the top surface of the package 202 and the second adhesive layer 108b on the top peripheral surface of the transparent cover 106, as shown in FIG. Figure 3 In some implementations, for example, for an optical sensor module 400 including an L-shaped fixing frame (e.g., fixing frame 410), the fixing frame is attached to the first adhesive layer 108a on the top surface of the package 202 and the first adhesive layer 108a on the top peripheral surface of the transparent cover 106, as shown. Figure 4A In some implementations, the fixing frame 210 is patterned to form fixing holes 412 before attaching the fixing frame 210 to the package 202, such as Figure 4B shown.

[0044] At 518, according to Figure 2 In some embodiments shown, method 500 includes injecting third adhesive layer 108 into the diagonal space between sidewall 212 and fixing frame 210. Third adhesive layer 108c also fills the remaining space between inclined sidewall 212 of package 202 and vertical side surface of transparent cover 106. The third adhesive layer thus fixes transparent cover 106 and fixing frame 210 to package 202.

[0045] In some implementations, the first adhesive layer 108a, the second adhesive layer 108b, and the third adhesive layer 108c can be cured after the optical sensor module structure is completed to harden the adhesive material. In some implementations, the curing operation can be completed by applying a heat treatment, which includes heating the adhesive layer 108 to a temperature of at least 70° C. Additionally or alternatively, the curing operation for some components of the adhesive layer 108 can include exposure to ultraviolet (UV) light.

[0046] As described above, an optical sensor module may include structural elements that allow light to enter an image sensor die while blocking moisture from reaching the image sensor die. A transparent cover mounted above the image sensor die provides protection for the die, while a fixed frame mounted above the transparent cover maintains the position of the transparent cover. Multiple bonding surfaces are used to increase the bonding strength between the fixed frame, the transparent cover, and the surrounding package. At the same time, a pre-molded package provides support around the periphery of the transparent cover while anchoring the fixed frame.

[0047] It should be understood that in the foregoing description, when an element such as a layer, a region or a substrate is mentioned as being on another element, connected to another element, electrically connected to another element, coupled to another element, or electrically coupled to another element, the element may be directly on another element, connected or coupled to another element, or one or more intermediate elements may be present. On the contrary, when an element is mentioned as being directly on another element or layer, directly connected to another element or layer, or directly coupled to another element or layer, there is no intermediate element or layer. Although the term directly on, directly connected to, or directly coupled to may not be used throughout the specific embodiments, an element that is shown as being directly on an element, directly connected, or directly coupled can be mentioned in this manner. The claims of the present application may be revised to narrate the exemplary relationships described in the specification or shown in the accompanying drawings.

[0048] As used in this specification, unless the context clearly indicates a particular case, the singular form may include the plural form. In addition to the orientations shown in the drawings, spatially relative terms (e.g., above, above, above, below, below, below, below, at the top, at the bottom, etc.) are intended to cover different orientations of the device in use or operation. In some specific implementations, the relative terms above and below may include vertically above and vertically below, respectively. In some specific implementations, the term adjacent can include lateral adjacent or horizontal adjacent.

[0049] Some implementations may be implemented using various semiconductor processing and / or packaging technologies. Some embodiments may be implemented using various types of semiconductor device processing technologies associated with semiconductor substrates, including but not limited to, for example, silicon (Si), silicon carbide (SiC), gallium arsenide (GaAs), gallium nitride (GaN), etc.

[0050] Although certain features of the described implementations have been described as described herein, many modifications, alternatives, variations, and equivalents will now occur to those skilled in the art. For example, features shown with respect to one implementation may also be included in other implementations where appropriate. Therefore, it should be understood that the appended claims are intended to cover all such modifications and variations that fall within the scope of the implementations. It should be understood that these modifications and variations are presented only by way of example and not limitation, and that various changes in form and detail may be made. In addition to mutually exclusive combinations, any portion of the apparatus and / or method described herein may be combined in any combination. The implementations described herein may include various combinations and / or sub-combinations of the functions, components, and / or features of the different implementations described.

Claims

1. A device, comprising: Lead frame; a semiconductor die coupled to the leadframe; an optically transparent cover spaced apart from the semiconductor die by a gap; a package surrounding the semiconductor die, the package being configured to support a perimeter of the optically transparent cover and coupled to the perimeter of the optically transparent cover by an encapsulant; and A perimeter frame is disposed on top of at least a portion of the perimeter of the optically transparent cover such that the optically transparent cover is fixedly coupled between the perimeter frame and the package.

2. The apparatus of claim 1, wherein the semiconductor die comprises an optical sensor.

3. The device of claim 2, wherein the optical sensor is a silicon photomultiplier tube. The device of claim 2 , wherein the optical sensor comprises a microlens array. The device of claim 1 , wherein the perimeter frame is coupled to a sidewall of the package through the encapsulant. The device of claim 1 , wherein the sealant is further disposed between the perimeter frame and the optically transparent cover.

7. The device of claim 1, wherein the perimeter frame and the optically transparent cover are disposed within a recessed area of ​​the package.

8. The device of claim 6, wherein the perimeter frame comprises a hardened liquid crystal polymer.

9. The device of claim 1, wherein the sealant comprises an organic epoxy material.

10. A method comprising: forming a lead frame having a base and leads; attaching a semiconductor die to the substrate; coupling the semiconductor die to the leads using wire bonds; forming an optical package around the leadframe, the semiconductor die, and the wire bonds; covering the semiconductor die with a glass cover; placing a peripheral frame on the glass cover; as well as The glass cover and the perimeter frame are secured to the optical package. 11 . The method of claim 10 , wherein providing the perimeter frame comprises securing the perimeter frame to the glass cover with an adhesive layer. The method of claim 10 , wherein forming the optical package comprises a pre-molding process. 13 . The method of claim 10 , wherein covering the semiconductor die with the glass cover comprises forming an air gap between the semiconductor die and the glass cover.

14. The method of claim 10, wherein securing the glass cover and the perimeter frame to the optical package comprises sealing with a layer of epoxy.

15. The method of claim 10, wherein securing the glass cover and the perimeter frame to the optical package extends a moisture permeation path to the air gap.

16. A tube die package, the tube die package comprising: Lead frame; a glass cover, the glass cover being suspended above the lead frame; a peripheral frame, the peripheral frame being on the glass cover; and An encapsulation material is configured to conform to the lead frame, the glass cover, and the perimeter frame. 17 . The die package of claim 16 , further comprising a sealant between the perimeter frame, the glass cover and the encapsulation material.

18. The die package of claim 17, wherein the perimeter frame comprises fixing holes to receive the encapsulant.

19. The die package of claim 16, wherein the encapsulation material comprises at least one of a pre-molded epoxy or a ceramic.

20. The die package of claim 16, wherein the perimeter frame is made of a rigid material.

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