Anti-glare semiconductor package and related methods

Abstract

The present invention is entitled "Anti-Glare Semiconductor Package and Related Methods." Embodiments of the semiconductor package may include a semiconductor die having a first side and a second side. The first side of an optically transmissive cover may be coupled to the second side of the semiconductor die via one or more barriers. The package may also include a photoresist material surrounding the semiconductor package, the photoresist material extending from the first side of the semiconductor die to the second side of the optically transmissive cover. The package may include an opening in the photoresist material on the second side of the optically transmissive cover, the opening substantially corresponding to an active area of ​​the semiconductor die.

Description

Technical Field

[0001] Aspects of this document generally relate to semiconductor packages, such as complementary metal oxide semiconductor (CMOS) image sensor chip scale packages (CISCSPs), for consumer electronic devices such as cameras, phones, tablets, and laptops. More specific embodiments relate to image sensor packages with lids. Background Art

[0002] Complementary Metal Oxide Semiconductor (CMOS) Image Sensor Chip Scale Package (CISCSP) has wide applications due to its small / thin form factor and low overall cost. Current CISCSPs include transparent glass covering the entire chip. Summary of the Invention

[0003] Embodiments of a semiconductor package may include a semiconductor die having a first side and a second side. The first side of an optically transmissive cover may be coupled to the second side of the semiconductor die via one or more stops. The package may also include a photoresist material surrounding the semiconductor package, the photoresist material extending from the first side of the semiconductor die to the second side of the optically transmissive cover. The package may include an opening in the photoresist material on the second side of the optically transmissive cover, the opening substantially corresponding to an active area of ​​the semiconductor die.

[0004] Embodiments of the semiconductor package may include one, all, or any of the following:

[0005] The second side of the optically transmissive cover may include an indentation on each of the first edge and the second edge of the optically transmissive cover.

[0006] The photoresist material may be a molding compound.

[0007] The semiconductor package may include a redistribution layer coupled to the first side of the semiconductor die.

[0008] The openings may correspond to an array of pixels in the semiconductor die.

[0009] The semiconductor package may further include one or more die pads coupled to each of the one or more dams.

[0010] The semiconductor package may further include one or more die pads coupled to each of the one or more dams.

[0011] The semiconductor package may also include a plurality of through silicon vias (TSVs), a passivation layer, a solder mask, and two or more solder bumps.

[0012] Embodiments of a semiconductor package may include: a semiconductor die having a first side and a second side; and a first side of an optically transmissive cover coupled to the second side of the semiconductor die via one or more stops. The second side of the optically transmissive cover may include first and second recesses located on first and second edges of the optically transmissive cover, respectively. The package may also include a photoresist material encapsulating the semiconductor package from the first side of the semiconductor die into the first and second recesses on the second side of the optically transmissive cover.

[0013] Embodiments of the semiconductor package may include one, all, or any of the following:

[0014] The semiconductor package may further include an opening in the photoresist material. The opening may be located between the first groove and the second groove on the second side of the optically transmissive cover.

[0015] The photoresist material may be a molding compound.

[0016] The semiconductor package may further include a redistribution layer (RDL) coupled to the first side of the semiconductor die.

[0017] An active area of ​​the semiconductor die may correspond to the first and second recesses in the optically transmissive glass cover.

[0018] The semiconductor package may further include one or more die pads coupled to each of the one or more dams.

[0019] The semiconductor package may also include a plurality of through silicon vias (TSVs), a passivation layer, a solder mask, and two or more solder bumps.

[0020] Embodiments of semiconductor packages may be formed using embodiments of a method for forming a semiconductor package, which may include providing an optically transmissive cover having a first side and a second side. The optically transmissive cover may include a plurality of recesses on the second side of the optically transmissive cover. The method may also include coupling a semiconductor wafer to the first side of the optically transmissive cover. The semiconductor wafer may include a first side and a second side. The second side of the wafer may include a plurality of active regions. The method may also include cutting the semiconductor wafer and the optically transmissive cover between each of the plurality of active regions in the wafer to form a plurality of semiconductor packages. The method may include coupling the second side of the optically transmissive cover of each semiconductor package in the semiconductor packages to a carrier wafer. The recesses in the optically transmissive cover may form a space between the carrier wafer and the optically transmissive cover. The method may include applying a photoresist material to each semiconductor package in the semiconductor packages. The photoresist material may encapsulate each semiconductor package in the semiconductor packages from the first side of the package into the recesses in the optically transmissive cover, including the recesses in the optically transmissive cover. The method may include cutting through the photoresist material to form a plurality of encapsulated semiconductor packages. The grooves may be on first and second edges of each of the optically transmissive covers around the opening in the photoresist material.

[0021] Implementations of methods of forming a semiconductor package may include one, all, or any of the following:

[0022] The method may include forming a plurality of grooves on the second side of the optically transmissive cover by one of etching or laser ablation.

[0023] The photoresist material may include a molding compound.

[0024] The method may further include forming a plurality of through silicon vias (TSVs), a passivation layer, a redistribution layer, a solder mask, and coupling a solder bump to each of the semiconductor packages.

[0025] The opening in the photoresist material on each of the plurality of semiconductor packages may correspond to an active area in the semiconductor die.

[0026] The method may further include coupling a stopper material to the optically transmissive cover.

[0027] The foregoing and other aspects, features, and advantages will be apparent to those skilled in the art from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Embodiments will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and:

[0029] Figure 1 is a cross-sectional view of an embodiment of a semiconductor package;

[0030] Figure 2 is a top view of an embodiment of a semiconductor package;

[0031] Figure 3 is a side view of an embodiment of an optically transmissive cover;

[0032] Figure 4 is a side view of an embodiment of a semiconductor wafer coupled with an embodiment of an optically transmissive cover;

[0033] Figure 5 is a side view of a panel of an embodiment of a semiconductor package after various processing steps;

[0034] Figure 6 is a cross-sectional view of the semiconductor package after dicing;

[0035] Figure 7 is a cross-sectional view of an embodiment of two semiconductor packages coupled using an embodiment of a carrier wafer;

[0036] Figure 8 is a cross-sectional view of an embodiment of two semiconductor packages after encapsulation with an embodiment of a photoresist material;

[0037] Figure 9 is a cross-sectional view of an embodiment of a semiconductor package after dicing; and

[0038] Figure 10 is a top view of an embodiment of a top portion of a semiconductor package as described herein. DETAILED DESCRIPTION

[0039] The present disclosure, its aspects, and embodiments are not limited to the specific components, assembly processes, or method elements disclosed herein. Many other components, assembly processes, and / or method elements known in the art that are consistent with the intended semiconductor package will readily be used with the specific embodiments of the present disclosure. Thus, for example, although the present disclosure discloses specific embodiments, such embodiments and implementation components may include any shape, size, style, type, model, version, measurement, concentration, material, quantity, method element, step, and / or the like known in the art for such semiconductor packages and implementation components and methods that are consistent with the intended operation and method.

[0040] In various image sensor embodiments, a transparent or translucent material is used to cover the exposed areas of the image sensor die. The transparent or translucent material of the cover or cap can allow light to enter the package outside the sensor area, which can result in glare being observed in the output of the image sensor. Figure 1 , shows an embodiment of a semiconductor package 2. The semiconductor package includes a semiconductor die 4 coupled to an optically transmissive cover 6. A second side of the semiconductor die 4 is coupled to a first side of the optically transmissive cover 6. In various embodiments, the optically transmissive cover 6 may include, as non-limiting examples, glass, polycarbonate, acrylic, plastic, or other materials that allow some or all of the desired wavelengths of light to pass through the material. In various embodiments, the optically transmissive cover may be coupled to the semiconductor die via an adhesive material. In various embodiments, the adhesive may include, as non-limiting examples, epoxies, resins, polymers, glues, solders, and other adhesive materials for coupling components of semiconductor devices. In some embodiments, the adhesive may include silver or other metal fillers to create conductivity for the adhesive. In some embodiments, a stopper 8 is coupled between the optically transmissive cover 6 and the semiconductor die 4. The stopper may create a gap between the cover and the active area of ​​the semiconductor die. In various embodiments, as non-limiting examples, the stopper material may include: liquid epoxy, silicone, or other encapsulant that provides device protection, reduces warping, exhibits excellent flow, provides good adhesion to multiple substrates, and has the strength to handle overmolding and subsequent process steps.

[0041] Still see Figure 1 , semiconductor package 2 also includes two through silicon vias (TSVs) 10 extending from the first side of the semiconductor die to a die pad 11 on the second side of semiconductor die 4. Coupled to the first side of semiconductor die 4 is a redistribution layer (RDL) 12 extending from a first edge of semiconductor die 4 to a second edge of semiconductor die 4. A ball grid array 14 is coupled to the first side of semiconductor die 4 and is surrounded by RDL 12.

[0042] As shown, the photoresist / masking material 16 surrounds the semiconductor package 2, extending from a first side of the semiconductor die 4 to a second side of the optically transmissive cover 6. The photoresist 16 does not completely encapsulate the semiconductor package. Figure 2 As shown, openings 18 in the photoresist material 16 are present on the second side of the optically transmissive cover 6, which substantially corresponds to the active area of ​​the semiconductor die (image sensor array). In various embodiments, the photoresist material can be a molding compound. In other embodiments, the photoresist material can include other materials such as epoxies, resins, or polymers that can block any desired frequency of light from entering through the side of the optically transmissive cover.

[0043] Photoresist can ensure that no light enters the semiconductor package from non-sensor areas. Blocking light from entering non-sensor areas prevents glare, which can degrade image sensor performance. Glare occurs when light bounces off metal features / metal structures within the semiconductor package and enters the sensor of the image sensor die. For example, after dicing, metal structures may be exposed in the die tracks of the semiconductor die. Without photoresist around the sides of the optically transmissive cover, light can enter the cover from many angles and reflect off the metal in the die tracks. Stray light can enter the cover directly, strike the metal structures, reflect around the cover, and then strike the sensor of the die. Applying photoresist around the edges of the optically transmissive cover creates a structure in which light can only enter the portion of the cover corresponding to the sensors or pixels of the semiconductor package, thereby preventing light from reaching any metal structures within the semiconductor package. By eliminating or substantially eliminating reflections from metal structures within the package, glare and the resulting image degradation caused by glare are also prevented.

[0044] As shown, the second side of the optically transmissive cover 6 has indentations 20 on each of the first edge 21 and the second edge 22 of the cover 6. The photoresist material 16 can fill these indentations, and the indentations 20 can prevent the photoresist material 16 from entering the opening 18. Figure 2 , shows a top view of opening 18 surrounded by photoresist material 16. Opening 18 may correspond to an array of pixels in a semiconductor die.

[0045] See also Figure 3 , shows a cross-sectional view of the optically transmissive cover 24. The optically transmissive cover 24 includes a plurality of grooves 26 formed on a first side of the cover. In some embodiments, the plurality of grooves may be pre-formed in the optically transmissive cover. In other embodiments, the plurality of grooves 26 may be formed by etching or laser ablation in combination with various patterning methods (such as photolithography). In various embodiments, etching may include wet etching or dry etching. Various embodiments of the method for manufacturing a semiconductor package as described herein may be used, including wafer-level processes and panel-level processes. Panel-level processes may have cost and productivity advantages. Panel-level processing may allow more units of semiconductor packages to be processed in parallel in a given cycle compared to wafer-level processes. Panel-level processing may also reduce waste resulting from processing partial dies in a wafer-level process. A method for forming a semiconductor package may include providing a method as described herein. Figure 3 In various embodiments, by way of non-limiting example, the optically transmissive cover may comprise glass, polycarbonate, acrylic, plastic, or other material that allows some or all of the desired wavelengths of light to pass through the material.

[0046] The method may also include coupling a semiconductor wafer to the first side of the optically transmissive cover. The semiconductor wafer may include a plurality of active areas formed on a second side of the wafer. In various embodiments, the active areas may include a pixel array. Figure 4 , shows a semiconductor wafer 28 coupled to an optically transmissive cover 24. A plurality of active areas 30 are enclosed in a gap 31 between the semiconductor material 28 and the optically transmissive cover 24. Stoppers 34 on either side of each of the plurality of active areas 32 facilitate forming the gap 31. In various embodiments, the stoppers 34 can be coupled to die pads 36 on either side of the active areas 30 in the semiconductor wafer 28.

[0047] refer to Figure 5 , an embodiment of a panel 37 of a semiconductor package is shown. In various embodiments, the panel can be processed using a standard chip scale packaging process. For example, the method may include forming a plurality of through silicon vias (TSVs) 38 through a first side of a semiconductor wafer on either side of an active area 30. The TSVs may be formed by drilling, etching, or other methods of forming holes through a semiconductor die. The method may further include forming a passivation layer and an RDL 40 over a plurality of semiconductor dies 43. The method may further include forming a solder mask and coupling a plurality of solder balls 42 to form a ball grid array (BGA) to a first side of the semiconductor die 43. In various embodiments, different surface mount interconnects may be used, such as, by way of non-limiting example, pillars, stud bumps, and any other interconnect type. In some embodiments, the interconnects may be formed of copper, solder, or other conductive materials.

[0048] The method may further include cutting the semiconductor wafer and the optically transmissive cover between each of the plurality of active regions in the wafer to form a plurality of semiconductor packages. The packages may be cut by sawing or dicing. Figure 6 , shows an embodiment of the semiconductor package 44 after dicing. The method also includes coupling each of the semiconductor packages to a carrier wafer. The second side of the optically transmissive cover 48 of each of the semiconductor packages 44 is coupled to the carrier wafer 49, as shown. Figure 7As shown. In various embodiments, the semiconductor packages can be coupled to the carrier wafer by a pick and place process. The grooves are located on the first edge and the second edge of each of the optically transmissive covers. As shown, the grooves 26 on the second side of each of the optically transmissive covers 24 form a space 46 between the carrier wafer 49 and the optically transmissive covers 24. The space is then filled with a photoresist material, thereby allowing the photoresist material to encapsulate each of the packages and leaving an opening on the second side of the optically transmissive covers. In various embodiments, the opening is sized to expose only the sensor area of ​​the semiconductor die. In other embodiments, the opening can be sized to expose substantially only the sensor area of ​​the semiconductor die.

[0049] See also Figure 8 , shows a plurality of semiconductor packages 44 after photoresist material 50 has been applied to each of the semiconductor packages. As previously described, the photoresist material 50 encapsulates each of the semiconductor packages from a first side of the package into and including the recess 26 on the optically transmissive cover 24. In various embodiments, the photoresist material 50 may comprise a molding compound. In various embodiments, by way of non-limiting example, the molding compound may comprise epoxy, resin, polymer, solder, and other materials that may be used to seal the die to the cover of the semiconductor package.

[0050] The photoresist material can prevent stray light from entering the active area of ​​the semiconductor die by preventing light from entering the semiconductor package on the side of the optically transmissive cover. In various embodiments, the method further includes cutting through the photoresist material to form a plurality of encapsulated semiconductor packages. The semiconductor packages can be cut by sawing or dicing.

[0051] See also Figure 9 , an embodiment of a semiconductor package 52 is shown. The package includes a semiconductor die 53 coupled to an optically transmissive cover 57. The semiconductor die 53 includes a first side 54 and a second side 56. The second side 56 of the semiconductor die 53 includes an active area having a pixel array. The second side 56 of the die 53 is coupled to the first side 59 of the optically transmissive cover 57. In various embodiments, the die and the cover can be coupled by an adhesive material. As non-limiting examples, the adhesive material can include: epoxy resin, resin, polymer, glue and other adhesive materials for coupling components of semiconductor devices. In other embodiments, the die and the cover can be coupled by a stopper. The stopper can be formed of any of the materials previously mentioned herein. The stopper creates a gap between the semiconductor die 53 and the optically transmissive cover 57.

[0052] The second side 58 of the optically transmissive cover 57 may include first and second grooves 60, 62 on a first edge 64 and a second edge 66 of the optically transmissive cover 57. The semiconductor package 52 also includes a photoresist material 68 that encapsulates the semiconductor package from the first side of the semiconductor die into the first and second grooves 60, 62 on the second side of the cover. Figure 10 , the opening 70 in the photoresist 68 is sized to expose only, or substantially only, the sensor area of ​​the semiconductor die. The size of the opening prevents stray light from entering the sensor area within the active area of ​​the semiconductor die. In various embodiments, the photoresist may comprise a molding compound. As previously described, in other embodiments, the photoresist may comprise other materials that block visible light from entering through the sides of the optically transmissive cover. The photoresist may ensure that no light enters the package from non-sensor areas of the semiconductor package. Blocking light from entering the non-sensor areas can prevent glare and enhance image quality.

[0053] See again Figure 9 The semiconductor package also includes a redistribution layer (RDL) 72 coupled to the first side of the semiconductor die 53. The RDL 72 is coupled to a die pad 74 through a plurality of through-silicon vias (TSVs) 76. As shown, the die pads are located on either side of the active area of ​​the image sensor die. The semiconductor package also includes a passivation layer, a solder mask, and two solder bumps 78 on the first side of the semiconductor die 53. In some embodiments, more than two bumps may be coupled to the first side of the semiconductor die.

[0054] Due to the presence of protection / molding on six sides of the semiconductor package, the embodiments of the semiconductor package described herein can have high reliability. The photoresist material and related processes can be used in other embodiments of image sensor packages, such as, as non-limiting examples, charge coupled device (CCD), complementary metal oxide semiconductor (CMOS), or N-type metal oxide semiconductor (NMOS, Live MOS) packages. It may be advantageous to apply the photoresist material to any semiconductor package that includes an optically transmissive cover to prevent unwanted light from entering the package.

[0055] Embodiments of semiconductor packages similar to those disclosed herein may include a redistribution layer coupled to the first side of the semiconductor die.

[0056] Embodiments of semiconductor packages similar to those disclosed herein may also include one or more die pads coupled to each of the one or more dams.

[0057] Embodiments of semiconductor packages similar to those disclosed herein may also include a plurality of through silicon vias (TSVs), a passivation layer, a solder mask, and two or more bumps.

[0058] Embodiments of semiconductor packages similar to those disclosed herein may include where the photoresist material is a molding compound.

[0059] Embodiments of a method of forming a semiconductor package may include forming a plurality of through silicon vias (TSVs), a passivation layer, a redistribution layer, a solder mask, and coupling a solder bump to each of the semiconductor packages.

[0060] Where reference is made in the above description to specific embodiments of semiconductor packages and implementation components, sub-components, methods and sub-methods, it should be apparent that various modifications may be made without departing from the essence thereof, and that these embodiments, implementation components, sub-components, methods and sub-methods may be applied to other semiconductor packages.

Claims

1. A semiconductor package, comprising: a semiconductor die comprising a first side and a second side; a first side of an optically transmissive cover coupled to a second side of the semiconductor die via one or more stops; a photoresist material included around the semiconductor package, the photoresist material extending from a first side of the semiconductor die to a second side of the optically transmissive cover; and an opening in the photoresist material on the second side of the optically transmissive cover, the opening corresponding to an active area of ​​the semiconductor die; Wherein the second side of the optically transmissive cover comprises an indentation on each of the first edge and the second edge of the optically transmissive cover. 2 . The semiconductor package of claim 1 , wherein the opening corresponds to a pixel array in the semiconductor die.

3. A semiconductor package comprising: a semiconductor die comprising a first side and a second side; a first side of an optically transmissive cover coupled to a second side of the semiconductor die via one or more stops, the second side of the optically transmissive cover comprising first and second grooves located on first and second edges of the optically transmissive cover, respectively; and A photoresist material encapsulates the semiconductor package from a first side of the semiconductor die into the first and second recesses of the second side of the optically transmissive cover. 4 . The semiconductor package of claim 3 , further comprising an opening in the photoresist material, the opening included between the first groove and the second groove on the second side of the optically transmissive cover. 5 . The semiconductor package of claim 3 , wherein an active area of ​​the semiconductor die corresponds to the first and second recesses in the optically transmissive cover.

6. A method of forming a semiconductor package, the method comprising: providing an optically transmissive cover comprising a first side and a second side, the optically transmissive cover comprising a plurality of grooves located on the second side of the optically transmissive cover; coupling a semiconductor wafer to the first side of the optically transmissive cover, the semiconductor wafer comprising a first side and a second side, the second side of the semiconductor wafer comprising a plurality of active areas; cutting the semiconductor wafer and the optically transmissive cover between each of the plurality of active regions in the semiconductor wafer to form a plurality of semiconductor packages; coupling a second side of the optically transmissive cover of each of the semiconductor packages to a carrier wafer, wherein the recess in the optically transmissive cover forms a space between the carrier wafer and the optically transmissive cover; applying a photoresist material to each of the semiconductor packages, the photoresist material encapsulating each of the semiconductor packages from a first side of the semiconductor package into the optically transmissive cover and including into the recess in the optically transmissive cover; as well as cutting through the photoresist material to form a plurality of encapsulated semiconductor packages; The groove is included around the opening in the photoresist material on a first edge and a second edge of each of the optically transmissive covers.

7. The method of claim 6, further comprising forming the plurality of grooves on the second side of the optically transmissive cover by one of etching or laser ablation. 8 . The method of claim 6 , wherein the opening in the photoresist material on each of the plurality of semiconductor packages corresponds to an active area in the semiconductor wafer.

9. The method of claim 6, further comprising coupling a stopper material to the optically transmissive cover.

Images