Power semiconductor device and bonding method thereof

Abstract

An apparatus includes: a backside support layer having a first thickness; an adhesive layer over the back side support layer; a metal layer over the adhesive layer, where the metal layer functions as a backside connector; the semiconductor substrate layer is arranged on the metal layer, and an active layer of the semiconductor substrate has a second thickness; and a plurality of front side connectors, wherein an active circuit in the semiconductor substrate layer is electrically coupled between the plurality of front side connectors and the metal layer.

Description

[0001] Cross-reference of related applications

[0002] This patent application claims priority to U.S. Application No. 18 / 882,721, filed September 11, 2024, entitled “Power Semiconductor Apparatus and Bonding Method Thereof,” and is expressly a continuation thereof, which is hereby incorporated herein by reference as if reproduced in its entirety. Technical Field

[0003] This disclosure generally relates to the field of integrated circuits, and in certain embodiments, to techniques and mechanisms for thin-wafer power semiconductor devices. Background Technology

[0004] Since the invention of integrated circuits, the semiconductor industry has experienced rapid growth due to the continuous increase in the integration density of various electronic components (such as transistors, diodes, resistors, capacitors, etc.). To a large extent, this increase in integration density comes from the iterative reduction of the minimum feature size, which allows more components to be integrated into a given area.

[0005] With the development of semiconductor technology, thin-wafer semiconductor devices have become an effective alternative for further reducing the physical size of semiconductor chips. For example, thin-wafer semiconductor devices are becoming increasingly important in space-constrained battery applications, such as in portable electronics and electric vehicles. These devices utilize ultra-thin silicon or other semiconductor materials to minimize thickness while maintaining high electrical performance. By reducing wafer thickness, these semiconductors can be integrated into compact battery systems, thereby increasing energy density without compromising functionality.

[0006] In semiconductor manufacturing processes, thin wafers face significant challenges due to their instability, lack of flatness, and susceptibility to breakage and stress during handling—all of which negatively impact device quality. Unsupported thin wafers often have non-planar, wavy profiles, making them unsuitable for subsequent manufacturing processes requiring flat surfaces. Furthermore, when thin wafers are unsupported during semiconductor assembly processes, they can lead to severe package warpage. This is because the inherent stresses in the thin wafer coupled to the support structure can cause uneven force distribution during packaging. As the wafer is handled, these stresses can become unbalanced, particularly when the wafer is released from its support or subjected to thermal cycling during assembly. This imbalance can cause the entire package to bend or warp, affecting the reliability of the final product and leading to problems such as poor electrical connections, impaired mechanical stability, and reduced overall performance of the semiconductor device. Therefore, there is a clear need for a support assembly that can accommodate thin wafers within existing processing systems. This disclosure addresses this need. Summary of the Invention

[0007] Technical advantages are typically achieved by describing embodiments of thin-wafer power semiconductor devices described in this disclosure.

[0008] According to an embodiment, a method includes: providing a device wafer having a first side bonded to a support wafer, wherein the device wafer includes a metal layer, a semiconductor substrate, a dielectric layer, and a plurality of connectors; providing a carrier, wherein the diameter of the carrier is the same as the diameter of the device wafer; applying an adhesive material to a second side of the device wafer to form a first adhesive layer; applying the adhesive material to the carrier to form a second adhesive layer; performing a partial curing process on the first adhesive layer and the second adhesive layer; bonding the device wafer to the carrier by bonding the first adhesive layer and the second adhesive layer together; and performing a full curing process on the adhesive material between the device wafer and the carrier.

[0009] According to another embodiment, an apparatus includes: a back-side support layer having a first thickness; an adhesive layer on the back-side support layer; a metal layer on the adhesive layer, wherein the metal layer serves as a back-side connector; a semiconductor substrate layer on the metal layer, wherein the semiconductor substrate layer has a second thickness; and a plurality of front-side connectors, wherein active circuitry in the semiconductor substrate layer is electrically coupled between the plurality of front-side connectors and the metal layer.

[0010] According to another embodiment, an apparatus includes: a back-side support layer having a first thickness; an adhesive layer on the back-side support layer; a metal layer on the cover layer, wherein the metal layer has a second thickness; and a semiconductor substrate layer on the metal layer, wherein the semiconductor substrate layer has a third thickness, wherein the first thickness of the back-side support layer is at least four times the third thickness of the semiconductor substrate layer, and the third thickness of the semiconductor substrate layer is greater than the second thickness of the metal layer.

[0011] The foregoing has provided a fairly broad overview of the features and technical advantages of this disclosure in order to better understand the detailed description of the following disclosure. Additional features and advantages of this disclosure, forming the subject matter of the claims, will be described below. Those skilled in the art will understand that the disclosed concepts and specific embodiments can be readily used as the basis for modifying or designing other structures or processes for carrying out the same purposes of this disclosure. Those skilled in the art will also recognize that such equivalent constructions do not depart from the spirit and scope of this disclosure as set forth in the appended claims. Attached Figure Description

[0012] To more fully understand this disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:

[0013] Figure 1 Perspective views illustrating the device chip and carrier according to various embodiments of the present disclosure;

[0014] Figure 2 This illustration shows perspective views of the device wafer and the carrier after an adhesive layer has been formed on them, according to various embodiments of the present disclosure.

[0015] Figure 3 This illustration shows a perspective view of the apparatus wafer and carrier when a partial curing process is applied to the adhesive layer according to various embodiments of the present disclosure;

[0016] Figure 4 Perspective views illustrating the bonding of a carrier and a device wafer according to various embodiments of the present disclosure;

[0017] Figure 5 This illustration shows perspective views of the device wafer and carrier after the support wafer has been peeled off from the device wafer, according to various embodiments of the present disclosure.

[0018] Figure 6 Cross-sectional views of device chips according to various embodiments of the present disclosure; and

[0019] Figure 7 A flowchart illustrating a method for bonding a device wafer to a carrier according to various embodiments of the present disclosure.

[0020] Unless otherwise indicated, corresponding numbers and symbols in different figures generally refer to corresponding parts. The figures are drawn to clearly illustrate relevant aspects of the embodiments and are not necessarily drawn to scale. Detailed Implementation

[0021] The making and use of embodiments of this disclosure are discussed in detail below. However, it should be understood that the concepts disclosed herein can be embodied in various specific contexts, and the specific embodiments discussed herein are merely illustrative and not intended to limit the scope of the claims. Furthermore, it should be understood that various changes, substitutions, and modifications may be made herein without departing from the spirit and scope of this disclosure as defined by the appended claims.

[0022] Furthermore, one or more features from one or more of the embodiments described below may be combined to create alternative embodiments not explicitly described, and features suitable for such combinations are understood to be within the scope of this disclosure. Therefore, the appended claims are intended to cover any such modifications or embodiments.

[0023] This disclosure is described with respect to embodiments in a specific context (i.e., thin-wafer power semiconductor devices). However, this disclosure is also applicable to a variety of power devices. Various embodiments will be explained in detail below with reference to the accompanying drawings.

[0024] Figure 1 This illustration shows a perspective view of a device wafer and carrier according to various embodiments of the present disclosure. Device wafer 101 is bonded to a support wafer 103. Device wafer 101 includes a metal layer, a semiconductor substrate, a passivation layer, and a plurality of connectors. In some embodiments, the passivation layer and the plurality of connectors are on a first side of the semiconductor substrate. The first side is also referred to as the front side of the semiconductor substrate. The metal layer is on a second side of the semiconductor substrate. The second side is also referred to as the back side of the semiconductor substrate. Depending on design requirements and different applications, a capping layer may be formed on the metal layer. The capping layer is formed of nickel. The metal layer is formed of copper. The nickel capping layer serves as a protective layer, ensuring the functionality and lifetime of the copper layer. Furthermore, a plurality of dielectric layers and interconnect structures are formed between the semiconductor substrate and the passivation layer. The interconnect structures provide necessary electrical connections between different components or regions of device wafer 101.

[0025] In some embodiments, the semiconductor substrate has been reduced to a thickness of approximately 50 micrometers (μm) using a suitable semiconductor thinning process, such as chemical mechanical planarization (CMP), polishing, etch-back, or any combination thereof. The metal layer has a thickness of approximately 30 μm. The total thickness of the device wafer 101 is approximately 80 μm. The support wafer 103 has a thickness greater than that of the device wafer 101. The support wafer 103 provides the necessary mechanical stability, thereby allowing the device wafer 101 to withstand the rigors of various semiconductor processing steps.

[0026] The carrier 102 is formed of silicon. Alternatively, the carrier 102 may be formed of other suitable materials, such as glass. In some embodiments, the diameter of the carrier 102 is the same as the diameter of the device wafer 101. The carrier 102 does not contain active devices (e.g., transistors) or passive devices (e.g., capacitors, resistors, inductors). Furthermore, the carrier 102 may also not contain conductive wires, such as metal wires.

[0027] In some embodiments, device chip 101 includes a plurality of device chips. Figure 1 The device wafer 101 shown is uncut and includes a semiconductor substrate. The semiconductor substrate extends continuously over the entire device wafer 101. According to some embodiments, the semiconductor substrate is formed of a polycrystalline silicon substrate. Alternatively, the semiconductor substrate may be formed of other semiconductor materials, such as silicon germanium, silicon carbide, and the like.

[0028] According to some embodiments, device chip 101 includes a plurality of active circuits. The active circuits are vertical power devices (e.g., vertical power MOSFETs, diodes). The vertical power devices are connected between a metal layer and a plurality of connectors. Alternatively, the active circuits are lateral power devices (e.g., lateral power MOSFETs, diodes). The active circuits are formed on the front side of a semiconductor substrate. Furthermore, the active circuits may be logic circuits (e.g., central processing unit (CPU), graphics processing unit (GPU), system-on-chip (SoC), application processor (AP), microcontroller, etc.), memory circuits (e.g., dynamic random access memory (DRAM) dies, static random access memory (SRAM) dies, etc.), power management circuits (e.g., power management integrated circuit (PMIC) dies), radio frequency (RF) circuits, sensor circuits (e.g., image sensors), microelectromechanical systems (MEMS) circuits, signal processing circuits (e.g., digital signal processing (DSP) dies), any combination thereof, and the like.

[0029] Figure 2 This illustration shows perspective views of the device wafer and carrier after an adhesive layer has been formed on them, according to various embodiments of the present disclosure. An adhesive material is applied to the metal layer of the device wafer 101 by a first spin coating process to form a first adhesive layer 201. Once the first spin coating process is complete, the thickness of the first adhesive layer 201 is approximately 15.21 μm. An adhesive material is also applied to the carrier 102 by a second spin coating process to form a second adhesive layer 202. Once the second spin coating process is complete, the thickness of the second adhesive layer 202 is approximately 15.21 μm.

[0030] Following spin coating, a soft baking process is applied to the first adhesive layer 201 and the second adhesive layer 202. The soft baking process is a heat treatment process applied to remove residual solvent and improve the adhesion of the first adhesive layer 201 to the metal layer of the device wafer 101 and the second adhesive layer 202 to the carrier 102. Specific conditions of the soft baking process may vary depending on design requirements. Generally, the soft baking process involves heating the coated device wafer and the coated carrier in an oven at a specific temperature for a set amount of time. In some embodiments, the temperature of the soft baking process is approximately 140 degrees Celsius. The soft baking time is approximately 5 minutes.

[0031] In some embodiments, the adhesive material is a polyimide adhesive material. The bonding temperature of the polyimide adhesive material is about 30 degrees Celsius. When the temperature applied to the polyimide adhesive material is less than 160 degrees Celsius, the polyimide adhesive material is semi-solid. After the full curing process, the polyimide adhesive material is solid. In some embodiments, the temperature of the full curing process is in the range of about 220 degrees Celsius to about 280 degrees Celsius. The full curing time is about 2 hours. After the full curing process is applied to the adhesive layer, the thickness of the adhesive layer may be varied. In some embodiments, the thickness of the adhesive layer is about 15.21 μm. After the full curing process, the thickness of the adhesive layer decreases to about 11.07 μm. The thickness shrinkage rate is about 27.26%.

[0032] Figure 3 This illustration shows a perspective view of a device wafer and carrier when a partial curing process is applied to an adhesive layer according to various embodiments of the present disclosure. Partial curing processes are typically used to reduce solvent and moisture content, which can enhance the adhesion and overall strength of the bond. This process typically involves applying heat to the adhesive material to remove residual solvent and moisture. After the partial curing process, the adhesive material is semi-solid. The material is subjected to higher temperatures to further reduce solvent content and eliminate moisture. This step also helps to crosslink the adhesive material, thereby enhancing its mechanical properties.

[0033] Figure 4 This is a perspective view illustrating the bonding of a carrier and a device wafer according to various embodiments of the present disclosure. During the bonding of the device wafer 101 to the carrier 102, the adhesive material is in a liquid phase at the bonding temperature.

[0034] During operation, after the device wafers are flipped, the two wafers are precisely aligned and brought into contact with each other. Adhesive material flows to fill any gaps between the surfaces, thereby ensuring uniform bonding. The stacked wafers are placed in a vacuum chamber to remove air and prevent voids from forming within the bonding lines. Once the vacuum is established, high pressure is applied to the device wafer 101 and the carrier 102. In some embodiments, the bonding pressure is approximately 1 millibar. Additionally, a bonding force of 1,000 Newtons is used to press the device wafer 101 and the carrier 102 together during the bonding process. The force is applied uniformly to the surfaces of the device wafer 101 and the carrier 102 to ensure uniform adhesive diffusion, thereby filling any gaps between the device wafer 101 and the carrier 102 to form an adhesive layer 203. This force is important for ensuring a strong, uniform bonding between the device wafer 101 and the carrier 102.

[0035] In some embodiments, the temperature of the bonding process is about 30 degrees Celsius. The bonding time is about 4 minutes.

[0036] Figure 5 This illustration shows perspective views of the device wafer and carrier after the support wafer has been peeled from the device wafer, according to various embodiments of the present disclosure. The support wafer 103 is peeled from the device wafer 101. Wafer peeling can be achieved using laser release, solvent release, or thermal release techniques.

[0037] like Figure 5 As shown, after the support chip 103 is peeled off from the device chip 101, the carrier 102 remains in the final structure.

[0038] A full curing process is applied to adhesive layer 203. The curing process ensures that the adhesive is fully polymerized or crosslinked, transforming from a liquid or semi-solid state to a solid state. This reaction strengthens the bond between device wafer 101 and carrier 102, thereby improving the mechanical integrity of the final structure. In some embodiments, the temperature of the full curing process is in the range of about 260 degrees to about 280 degrees. The full curing time is about 2 hours.

[0039] After a suitable cutting process (e.g., sawing), the final structure comprising device wafer 101, adhesive layer 203 and carrier 102 is divided into a plurality of individual device chips, each of which represents a complete functional unit that can be packaged and used in an electronic device.

[0040] Figure 6 This is a cross-sectional view of a device chip according to various embodiments of the present disclosure. The device chip includes a back support side 601, an adhesive layer 203, a cover layer 602, a metal layer 604, a semiconductor substrate 610, a passivation layer 612, and a plurality of connectors 621, 622, and 623.

[0041] Figure 6 The back support layer 601 shown in the image is Figure 5 The image shows a workpiece on carrier 102. For example... Figure 6 As shown in the diagram, after the cutting process has been executed, the workpiece of the carrier 102 is the outermost layer of the corresponding device chip.

[0042] Adhesive layer 203 is a dielectric layer formed of polyimide adhesive material. This polyimide adhesive material has been described above regarding... Figure 2 The description is omitted here, and therefore will not be discussed further in this article.

[0043] The capping layer 602 is formed of nickel. The capping layer serves as a protective layer, ensuring the function and lifespan of the metal layer 604.

[0044] Metal layer 604 is formed of copper. Metal layer 604 serves as a back-side connector electrically connected to active circuitry in semiconductor substrate 610. In some embodiments, the active circuitry in semiconductor substrate 610 is a plurality of diodes. Metal layer 604 is electrically connected to the cathodes or anodes of the plurality of diodes. In an alternative embodiment, the active circuitry in semiconductor substrate 610 is a plurality of back-to-back connected transistors. Metal layer 604 is electrically connected to the shared drain or shared source of the plurality of back-to-back connected transistors.

[0045] The semiconductor substrate 610 may be doped or undoped silicon, or an active layer of a semiconductor-on-insulator substrate. The semiconductor substrate 610 may contain other semiconductor materials, such as germanium, silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, indium arsenide and / or indium antimonide, any combination thereof, and the like.

[0046] An interlayer dielectric (ILD) layer (not shown) may be present on the active surface of the semiconductor substrate 610. The ILD layer may comprise one or more dielectric layers formed of materials such as phosphosilicate glass (PSG), borosilicate glass (BSG), boron-doped phosphosilicate glass (BPSG), undoped silicate glass (USG), or similar materials. The dielectric material may be deposited using spin coating, chemical vapor deposition (CVD), or plasma-enhanced CVD (PECVD) techniques.

[0047] Multiple metallization layers (not shown) may be formed on the ILD layer. The metallization layers are used to interconnect various active circuits in the semiconductor substrate 610 and further provide electrical connections between the active circuits and external circuits (not shown).

[0048] A passivation layer 612 is formed on the semiconductor substrate 610. The passivation layer 612 may be formed from one or more suitable dielectric materials, such as silicon oxide, silicon nitride, low-k dielectrics (e.g., carbon-doped oxides), very low-k dielectrics (e.g., porous carbon-doped silicon dioxide), polymers (e.g., polyimide), solder resists, polybenzoxazole (PBO), benzocyclobutene (BCB)-based polymers, molding compounds, any combination thereof, and the like. The passivation layer 612 may be formed by spin coating, lamination, CVD, any combination thereof, and the like.

[0049] Connectors 621, 622, and 623 are formed to extend through the passivation layer 612 to be physically and electrically coupled to the semiconductor substrate 610. Alternatively, connectors 621, 622, and 623 may be electrically coupled to the semiconductor substrate 610 via interconnect structures in a metallization layer. Connectors 621, 622, and 623 are formed of conductive materials, such as aluminum, copper, tungsten, silver, gold, combinations thereof, and / or similar materials.

[0050] In some embodiments, the back-side support layer 601 has a first thickness ranging from about 200 μm to about 725 μm. The metal layer 604 has a second thickness of about 30 μm. The semiconductor substrate 610 has a third thickness of about 50 μm.

[0051] In some embodiments, Figure 6 The total thickness of the device chip shown should be less than 200 μm. To achieve this thickness, a thinning process is performed on the back-side support layer 601. The thinning process can be a mechanical polishing process, a chemical polishing process, an etching process, or the like. By employing a thinning process, the back-side support layer 601 can be polished, so that the thickness of the back-side support layer 601 can be reduced from about 725 μm to about 200 μm.

[0052] Figure 7 A flowchart illustrating a method for bonding a device wafer to a carrier according to various embodiments of the present disclosure. Figure 7 The flowchart shown is merely an example and should not unduly limit the scope of the claims. Those skilled in the art will recognize many variations, substitutions, and modifications. For example, additions, removals, substitutions, rearrangements, and repetitions may be made. Figure 7 The various steps described in the document.

[0053] At step 702, a device wafer is provided. The device wafer has a first side bonded to a support wafer. The device wafer includes a metal layer, a semiconductor substrate, a dielectric layer, and a plurality of connectors.

[0054] At step 704, a carrier is provided. The diameter of the carrier is the same as the diameter of the device wafer.

[0055] At step 706, an adhesive material is applied to the second side of the device wafer to form a first adhesive layer.

[0056] In step 708, adhesive material is applied to the carrier to form a second adhesive layer.

[0057] In step 710, a partial curing process is performed on the first adhesive layer and the second adhesive layer.

[0058] At step 712, the device wafer is bonded to the carrier.

[0059] In step 714, a complete curing process is performed on the adhesive material between the device wafer and the carrier.

[0060] The method further includes peeling the support wafer from the device wafer after the device wafer is bonded to the carrier wafer and before a full curing process is performed on the adhesive material.

[0061] The method further includes performing a dicing process after a complete curing process on the adhesive material to separate multiple chips in the device wafer into multiple packages, each of the multiple packages including a carrier workpiece.

[0062] After the cutting process has been performed, the workpiece of the carrier is the outermost layer of the corresponding package.

[0063] The method further includes: performing a partial curing process on an adhesive material on a second side of the device wafer and on a carrier at a first temperature; bonding the device wafer to the carrier at a second temperature; and performing a full curing process on the adhesive material at a third temperature, wherein the third temperature is at least 100 degrees higher than the first temperature, and the first temperature is at least 100 degrees higher than the second temperature.

[0064] The first temperature is about 140 degrees, the second temperature is about 30 degrees, and the third temperature is about 260 degrees.

[0065] Before the adhesive material undergoes a full curing process, the adhesive layer between the device wafer and the carrier has a first thickness. After the adhesive material undergoes a full curing process, the adhesive layer between the device wafer and the carrier has a second thickness. The metal layer has a third thickness, wherein the first thickness is greater than the third thickness, and the third thickness is greater than the second thickness.

[0066] The adhesive material is a polyimide adhesive material.

[0067] The metal layer is in direct contact with the semiconductor substrate and serves as a connector for active circuits electrically coupled into the semiconductor substrate.

[0068] The method further includes bonding the device wafer to the carrier using liquid phase bonding under high pressure in a vacuum.

[0069] Although the description has been detailed, it should be understood that various changes, substitutions, and alterations may be made without departing from the spirit and scope of this disclosure as defined by the appended claims. Furthermore, the scope of this disclosure is not intended to be limited to the specific embodiments described herein, and those skilled in the art will readily understand from this disclosure that existing or future-developed processes, machines, manufactures, components, methods, or steps can be utilized to perform substantially the same functions or achieve substantially the same results as the corresponding embodiments described herein. Therefore, the appended claims are intended to encompass such processes, machines, manufactures, components, methods, or steps within their scope.

Claims

1. A method comprising: A device wafer having a first side bonded to a support wafer is provided, wherein the device wafer includes a metal layer, a semiconductor substrate, a dielectric layer and a plurality of connectors; A carrier is provided, wherein the diameter of the carrier is the same as the diameter of the device wafer; An adhesive material is applied to the second side of the device wafer to form a first adhesive layer; The adhesive material is applied to the carrier to form a second adhesive layer; A partial curing process is performed on the first adhesive layer and the second adhesive layer; The device wafer is bonded to the carrier by bonding the first adhesive layer and the second adhesive layer together; and A complete curing process is performed on the adhesive material between the device wafer and the carrier.

2. The method according to claim 1, wherein: After the device wafer is bonded to the carrier wafer and before the full curing process is performed on the adhesive material, the support wafer is peeled off from the device wafer.

3. The method according to claim 1 or claim 2, further comprising: After the complete curing process is performed on the adhesive material, a dicing process is performed to separate multiple chips in the device wafer into multiple packages, each of which includes a workpiece of the carrier.

4. The method according to claim 3, wherein: At a time after the cutting process has been performed, the workpiece of the carrier is the outermost layer of the corresponding package.

5. The method according to any one of claims 1 to 4, further comprising: At a first temperature, the partial curing process is performed on the adhesive material on the second side of the device wafer and on the carrier; At a second temperature, the device wafer is bonded to the carrier; and The complete curing process is performed on the adhesive material at a third temperature, wherein: The third temperature is at least 100 degrees higher than the first temperature; and The first temperature is at least 100 degrees higher than the second temperature.

6. The method according to claim 5, wherein: The first temperature is approximately 140 degrees Celsius; The second temperature is approximately 30 degrees Celsius; and The third temperature is approximately 260 degrees Celsius.

7. The method according to any one of claims 1 to 6, wherein: Before the complete curing process is performed on the adhesive material, the adhesive layer between the device wafer and the carrier has a first thickness; After the complete curing process is performed on the adhesive material, the adhesive layer between the device wafer and the carrier has a second thickness; and The metal layer has a third thickness, and wherein: The first thickness is greater than the third thickness; and The third thickness is greater than the second thickness.

8. The method according to any one of claims 1 to 7, wherein: The adhesive material is a polyimide adhesive material.

9. The method according to any one of claims 1 to 8, wherein: The metal layer is in direct contact with the semiconductor substrate; and The metal layer serves as a connector for active circuitry electrically coupled to the semiconductor substrate.

10. The method according to any one of claims 1 to 9, further comprising: The device wafer is bonded to the carrier using liquid phase bonding in a vacuum under high pressure.

11. An apparatus comprising: A back support layer having a first thickness; An adhesive layer is placed on the back support layer; A metal layer, which is on top of the adhesive layer, wherein the metal layer serves as a back-side connector; A semiconductor substrate layer on top of the metal layer, wherein the semiconductor substrate layer has a second thickness; and Multiple front-side connectors, wherein active circuitry in the semiconductor substrate is electrically coupled between the multiple front-side connectors and the metal layer.

12. The apparatus of claim 11, further comprising: A cover layer is formed between the adhesive layer and the metal layer; and A passivation layer is placed on the semiconductor substrate.

13. The apparatus according to claim 11 or 12, wherein: The adhesive layer is formed of a polyimide adhesive material, wherein the polyimide adhesive material is semi-solid before a curing process is applied to the polyimide adhesive material.

14. The apparatus according to any one of claims 11 to 13, wherein: The first thickness of the back-side support layer is at least four times the second thickness of the semiconductor substrate layer.

15. The apparatus according to any one of claims 11 to 14, wherein: The metal layer has a third thickness; and The adhesive layer has a fourth thickness, and wherein: The second thickness of the semiconductor substrate layer is greater than the third thickness of the metal layer; and The third thickness of the metal layer is greater than the fourth thickness of the adhesive layer.

16. An apparatus comprising: A back support layer having a first thickness; An adhesive layer is placed on the back support layer; A metal layer, which is on the cover layer, wherein the metal layer has a second thickness; and A semiconductor substrate layer, situated on top of the metal layer, wherein the semiconductor substrate layer has a third thickness, wherein: The first thickness of the back-side support layer is at least four times the third thickness of the semiconductor substrate layer; and The third thickness of the semiconductor substrate is greater than the second thickness of the metal layer.

17. The apparatus according to claim 16, wherein: The first thickness is in the range of approximately 200 μm to approximately 725 μm; The second thickness is approximately 30 μm; and The third thickness is approximately 50 μm.

18. The device according to claim 16 or 17, further comprising a cover layer formed between the adhesive layer and the metal layer, wherein: The metal layer is formed of copper; and The cover layer is formed of nickel.

19. The device according to any one of claims 16 to 18, further comprising: A passivation layer is formed on the semiconductor substrate layer; and Multiple connectors are formed on the passivation layer.

20. The apparatus according to claim 19, wherein: The semiconductor substrate includes a plurality of active circuits electrically coupled between the plurality of connectors and the metal layer.

21. The device according to any one of claims 16 to 20, wherein: The first thickness of the back-side support layer is at least four times the third thickness of the semiconductor substrate layer.

22. The device according to any one of claims 16 to 21, wherein: The adhesive layer has a fourth thickness, and wherein: The third thickness of the semiconductor substrate layer is greater than the second thickness of the metal layer; and The second thickness of the metal layer is greater than the fourth thickness of the adhesive layer.

23. The device according to any one of claims 16 to 22, wherein: The adhesive layer is formed of a polyimide adhesive material.

24. The device according to any one of claims 16 to 23, wherein: The metal layer is in direct contact with the semiconductor substrate.

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