Adhesive-free bonding of substrate to carrier

Abstract

Methods for bonding and debonding a thin substrate film to and from a carrier are provided herein. In some embodiments, a method for processing a semiconductor substrate includes: applying a non-sticky polymer layer to a carrier formed of a dielectric material. Then applying a second layer to the polymer layer. Then forming one or more redistribution layers on the second layer. Then separating the second layer from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion.

Description

Technical Field

[0001] Embodiments of the present principles generally relate to semiconductor processing used in packaging semiconductor devices. Background Art

[0002] Semiconductor substrates are processed to form structures on the surface of the substrate. The structures on specific areas of the substrate can be linked together to form microcircuits. The substrate can have many different microcircuits constructed on the surface of the substrate during processing. Once the processing of the substrate is completed, the substrate is cut or singulated to separate the microcircuits into semiconductor "chips" or dies. The substrate undergoes many processes before the final chip is developed. Some of these processes include physical vapor deposition (PVD), photolithography, and thermal curing.

[0003] Chips usually contain complex circuits and need to interact with external components. The internal circuits of the chip are too fine to be directly connected to external components. In order to overcome the external connection problem, lead outs are formed, which are connected to the internal circuits of the chip to pads or solder balls, thereby allowing external connections. During the subsequent packaging process of the semiconductor chip, the lead outs are formed in the so-called redistribution layer. Before these processes, the substrate undergoes a temporary bonding process. Typically, the temporary bonding process includes dispensing a liquid adhesive onto a glass carrier, followed by attaching a thin substrate film to the bonding surface before undergoing compression and thermal curing. Once the bonded substrate completes the production process, the substrate can be released from the glass carrier via an ultraviolet or laser method that decomposes the cured adhesive. However, temporary bonding and disengagement are expensive and time-consuming. In addition, the technology using a temporary carrier also requires additional processing steps, which increases costs and reduces the yield of the redistribution layer process.

[0004] Accordingly, the inventors have provided improved methods and apparatus for bonding and debonding thin substrate films to a carrier. Summary of the invention

[0005] Methods for bonding and debonding a thin substrate film to and from a carrier are provided herein. In some embodiments, a method for processing a semiconductor substrate includes: applying a non-stick polymer layer to a carrier formed of a dielectric material; applying a second layer to the polymer layer; forming one or more redistribution layers on the second layer; and separating the second layer from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion.

[0006] In some embodiments, a method of forming a package includes: applying a non-adhesive interface layer to a carrier formed of a dielectric material; forming one or more redistribution layers on the interface layer; coupling an integrated circuit to the one or more redistribution layers; and separating the one or more redistribution layers and the integrated circuit from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion.

[0007] In some embodiments, a method for processing a semiconductor substrate includes: applying a non-stick interface layer to a dielectric carrier, wherein the interface layer includes a first polymer layer and a second layer; forming one or more redistribution layers on the second layer; separating the second layer from the dielectric carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion; and removing at least one of the first polymer layer and the second layer from the one or more redistribution layers.

[0008] In some embodiments, a non-transitory computer-readable storage medium stores a program that causes a computer or a processing chamber to execute a method for processing a semiconductor substrate, the method comprising: applying a non-sticky polymer layer to a carrier formed of a dielectric material; applying a second layer to the polymer layer; forming one or more redistribution layers on the second layer; and separating the second layer from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion.

[0009] Other and further embodiments of the disclosure are described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The embodiments of the present disclosure briefly summarized above and discussed in more detail below may be understood by reference to the illustrative embodiments of the present disclosure depicted in the accompanying drawings. However, the accompanying drawings show only typical embodiments of the present disclosure and therefore should not be considered limiting of the scope, as the present disclosure may allow other equally effective embodiments.

[0011] Figure 1 Methods of bonding and debonding a thin substrate film to and from a carrier according to some embodiments of the present disclosure.

[0012] Figures 2A-2F Depicted are stages of a process of bonding and debonding a thin substrate film to and from a carrier board according to some embodiments of the present disclosure.

[0013] Figures 3A-3F Depicted are stages of a process of bonding and debonding a thin substrate film to and from a carrier board according to some embodiments of the present disclosure.

[0014] To facilitate understanding, identical reference numerals have been used, where possible, to denote identical components common to the drawings. The drawings are not drawn to scale and may be simplified for clarity. Components and features of one embodiment may be beneficially incorporated into other embodiments without further description. DETAILED DESCRIPTION

[0015] A semiconductor package is a metal, plastic, glass or ceramic housing containing one or more semiconductor electronic components. Fan-out wafer level packaging (FOWLP) is an advanced semiconductor package used by the semiconductor industry. The FOWLP package includes a redistribution layer formed on a substrate. The substrate consists of a carrier bonded to a thin substrate film. In some embodiments, the carrier has an outer diameter of about 12 inches. The integrated circuit chip is then coupled to one or more redistribution layers. The integrated circuit chip is then encapsulated with an epoxy mold compound. These series of processes can be repeated again to complete the upper portion of the package assembly. Finally, the package assembly is released or disengaged from the carrier via various methods (such as infrared exposure, magnetic induction heating, or electrostatic repulsion).

[0016] The inventors have discovered that a reversible bonding layer can advantageously bond a wafer film to a carrier, such as a silicon carrier. In an embodiment, a sacrificial layer can be used to bond a thin wafer to a carrier, such as a silicon carrier, before releasing the bonded wafer to downstream processing.

[0017] Figure 1 The present invention is a method of bonding and debonding a thin substrate film to and from a carrier according to some embodiments of the present disclosure. The method 100 begins at 102 by applying a non-adhesive interface layer to a carrier. In some embodiments, the non-adhesive interface layer does not include an adhesive; however, the non-adhesive interface layer can be bonded to the carrier as described below. The interface layer advantageously provides low outgassing, high thermal stability, high chemical resistance, and high bond strength. In some embodiments, as Figure 2A-2BAs shown, the interface layer 218 includes a polymer layer 204 and a second layer 206. In some embodiments, the polymer layer 204 is non-sticky and is applied to the carrier 202. In some embodiments, the polymer layer 204 is not a sticky layer and is characterized as being non-sticky; however, when the non-sticky layer is applied to the carrier 202, the non-sticky layer can be bonded to the carrier 202. In some embodiments, the carrier 202 is coated with the polymer layer 204 and then subsequently cured. In some embodiments, the carrier 202 is formed of a dielectric material. In some embodiments, the carrier 202 includes silicon. In some embodiments, the polymer layer 204 includes polydimethylsiloxane (PDMS) doped with nanoparticles, etc. The nanoparticles are configured to generate heat when the nanoparticles are exposed to magnetic induction heating or infrared exposure. In some embodiments, the second layer 206 is deposited on the polymer layer 204. In some embodiments, the second layer 206 is a substantially pure or pure polydimethylsiloxane (PDMS) layer.

[0018] In some embodiments, Figure 3A-3B As shown, the interface layer 318 includes a polymer layer 304 and a second layer 306. In some embodiments, the polymer layer 304 is non-sticky and is applied to the carrier 302. In some embodiments, the polymer layer 304 is not a sticky layer and is characterized as non-sticky; however, in some embodiments, the non-sticky layer is configured to bond to the carrier 302 when applied to the carrier 302. In some embodiments, the carrier 302 is configured as an electrostatic chuck, which includes electrodes (such as first electrode 320 and second electrode 330) embedded in the carrier 302. In some embodiments, the carrier 302 includes a ceramic material. In some embodiments, the polymer layer 304 includes a semi-conductive polymer film. In some embodiments, the second layer 306 is formed of a conductive material. In some embodiments, the second layer 306 is a copper layer. The polymer layer 304 advantageously helps to bond the second layer 306 to the carrier 302. In operation, the first electrode 320 and the second electrode 330 of the carrier 302 are charged to generate an electrostatic attraction force between the carrier 302 and the second layer 306. The charges of the first electrode 320 and the second electrode 330 have opposite polarities to electrostatically clamp or bond the second layer 306 to the carrier 302. For example, the first electrode 320 may have a positive polarity and the second electrode 330 may have a negative polarity.

[0019] refer to Figure 1 In some embodiments, the method continues at 104 by forming one or more redistribution layers on the interface layer 218. In some embodiments, as Figure 2CAs shown, one or more redistribution layers 208 are formed on the second layer 206. In some embodiments, an integrated circuit chip 210 is coupled to the one or more redistribution layers 208. The integrated circuit chip 210 is encapsulated with an epoxy mold compound 212. In some embodiments, as shown in FIG. Figure 3C As shown, one or more redistribution layers 308 are formed on the second layer 306. In some embodiments, an integrated circuit chip 310 is coupled to the one or more redistribution layers 308. The integrated circuit chip 310 is encapsulated with an epoxy mold compound 312.

[0020] In some embodiments, the method continues at 106 by separating the second layer from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion. In some embodiments, the method continues at 106 by separating the interface layer including the second layer from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion. Figure 2D As shown, a magnetic field 214 is applied to the interface layer 218. The magnetic field 214 can be generated by a permanent magnet, an electromagnet, etc. The magnetic field 214 is advantageously positioned to target heating of the nanoparticles embedded in the polymer layer 204. The magnetic field 214 is configured to not thermally affect the one or more redistribution layers 208. In some embodiments, the nanoparticles are configured to generate heat when the nanoparticles are exposed to magnetic induction heating. In some embodiments, as Figure 2E As shown, the heating of the nanoparticles causes the second layer 206 to separate from the polymer layer 204 and the carrier 202. Thus, in some embodiments, the bond between the second layer 206 and the polymer layer 204 can be characterized as temporary or reversible. In some embodiments, the second layer 206 is exposed to infrared radiation to heat the nanoparticles to separate the second layer 206 from the polymer layer 204 and the carrier 202.

[0021] In some embodiments, Figure 3D-3E As shown, the first electrode 320 and the second electrode 330 of the carrier 302 are charged to induce an electrostatic repulsive force between the carrier 302 and the second layer 306. The charge of the first electrode 320 and the second electrode 330 has the same polarity as the charge of the second layer 306 to separate or debond the second layer 306 from the carrier 302. For example, the first electrode 320 and the second electrode 330 can both have a positive polarity. In some embodiments, heat is applied to the interface layer 318 to enhance the debonding process.

[0022] Reference Figure 1 In some embodiments, method 100 continues at 108 by removing any remaining material of the interface layer from the one or more redistribution layers. Figure 2FAs shown, the second layer 206 is removed from the one or more redistribution layers 208. In some embodiments, the second layer 206 can be removed by peeling. In some embodiments, the second layer 206 can be removed by chemical treatment. In some embodiments, as Figure 3F As shown, polymer layer 304 is removed from one or more redistribution layers 308. In some embodiments, polymer layer 304 can be removed by stripping. In some embodiments, polymer layer 304 can be removed via chemical treatment.

[0023] In some embodiments, the present disclosure relates to a method for processing a semiconductor substrate, comprising: applying a non-sticky polymer layer to a carrier formed of a dielectric material; applying a second layer to the polymer layer; forming one or more redistribution layers on the second layer; and separating the second layer from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion, wherein the carrier is configured as an electrostatic chuck, the electrostatic chuck includes an electrode embedded in the carrier, and the polymer layer includes a semiconductive polymer film, wherein the method further includes causing an electrostatic attraction force between the carrier and the second layer before forming the one or more redistribution layers. In some embodiments, the second layer is a copper layer. In some embodiments, the method further includes storing a charge of opposite polarity in the electrode before forming the one or more redistribution layers to electrostatically clamp the second layer to the carrier. In some embodiments, the method further includes applying a charge of the same polarity to the electrode and the second layer to separate the second layer from the carrier. In some embodiments, both the polymer layer and the second layer include polydimethylsiloxane (PDMS). In some embodiments, the polymer layer includes polydimethylsiloxane (PDMS) doped with nanoparticles, and the nanoparticles are configured to generate heat when the nanoparticles are exposed to magnetic induction heating or infrared exposure. In some embodiments, the carrier comprises silicon.

[0024] In some embodiments, the present disclosure relates to a method for processing a semiconductor substrate, comprising: applying a non-stick polymer layer to a carrier formed of a dielectric material; applying a second layer to the polymer layer; forming one or more redistribution layers on the second layer; and separating the second layer from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion, wherein the polymer layer comprises polydimethylsiloxane (PDMS) doped with nanoparticles, the nanoparticles being configured to generate heat when the nanoparticles are exposed to magnetic induction heating or infrared exposure, wherein the second layer is a substantially pure polydimethylsiloxane (PDMS) layer, and wherein the second layer is separated from the polymer layer and the carrier via at least one of magnetic induction heating or infrared exposure to heat the nanoparticles.

[0025] In some embodiments, the present disclosure relates to a non-transitory computer-readable storage medium storing a program that causes a computer or a processing chamber to execute the following: a method of processing a semiconductor substrate according to the present disclosure, such as including: applying a non-sticky polymer layer to a carrier formed of a dielectric material; applying a second layer to the polymer layer; forming one or more redistribution layers on the second layer; and separating the second layer from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion.

[0026] In some embodiments, the present disclosure relates to a non-transitory computer-readable storage medium storing a program that causes a computer or a processing chamber to perform the following: a method of forming a package, comprising: applying a non-adhesive interface layer to a carrier formed of a dielectric material; forming one or more redistribution layers on the interface layer; coupling an integrated circuit to the one or more redistribution layers; and separating the one or more redistribution layers and the integrated circuit from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion.

[0027] In some embodiments, the present disclosure relates to a method for processing a semiconductor substrate, comprising: applying a non-sticky interface layer to a dielectric carrier, wherein the interface layer comprises a first polymer layer and a second layer; forming one or more redistribution layers on the second layer; separating the second layer from the dielectric carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion; and removing at least one of the first polymer layer and the second layer from the one or more redistribution layers. In some embodiments, the first polymer layer comprises polydimethylsiloxane (PDMS) doped with nanoparticles, the nanoparticles being configured to generate heat when the nanoparticles are exposed to magnetic induction heating or infrared exposure. In some embodiments, the dielectric carrier is configured as an electrostatic chuck, the electrostatic chuck comprising an electrode embedded in the dielectric carrier, and the interface layer comprises a semiconductive polymer film, and further comprising causing an electrostatic attraction force between the dielectric carrier and the second layer before forming the one or more redistribution layers.

[0028] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof.

Claims

1. A method for processing a semiconductor substrate, comprising: applying a non-stick polymer layer to a carrier formed of a dielectric material; applying a second layer to the polymer layer; forming one or more redistribution layers on the second layer; and The second layer is separated from the carrier through at least one of magnetic induction heating, infrared exposure or electrostatic repulsion.

2. The method of claim 1 , wherein the carrier is configured as an electrostatic chuck, the electrostatic chuck comprises an electrode embedded in the carrier, and the polymer layer comprises a semiconductive polymer film, and further comprising: inducing an electrostatic attraction force between the carrier and the second layer before forming the one or more redistribution layers. The method of claim 2 , wherein the second layer is a copper layer.

4. The method of claim 2 or 3, further comprising: before forming the one or more redistribution layers, storing charges of opposite polarity in the electrodes to electrostatically clamp the second layer to the carrier. 5 . The method of claim 4 , further comprising applying charges having the same polarity to the electrode and the second layer to separate the second layer from the carrier.

6. The method of any one of claims 1 to 5, wherein the polymer layer and the second layer both comprise polydimethylsiloxane (PDMS).

7. The method of claim 6, wherein the polymer layer comprises polydimethylsiloxane (PDMS) doped with nanoparticles configured to generate heat when the nanoparticles are exposed to magnetic induction heating or infrared light exposure.

8. A method as described in any one of claims 1 to 7, wherein the polymer layer comprises polydimethylsiloxane (PDMS) doped with nanoparticles, the nanoparticles being configured to generate heat when the nanoparticles are exposed to magnetic induction heating or infrared exposure, wherein the second layer is a substantially pure polydimethylsiloxane (PDMS) layer, and wherein the second layer is separated from the polymer layer and the carrier by heating the nanoparticles via at least one of magnetic induction heating or infrared exposure.

9. A method of forming a package, comprising: applying a non-stick interface layer to a carrier formed of a dielectric material, the interface layer comprising a first polymer layer; forming one or more redistribution layers on the interface layer; coupling an integrated circuit to the one or more redistribution layers; as well as The one or more redistribution layers and the integrated circuit are separated from the carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion.

10. The method of claim 9, wherein applying the interface layer to the carrier comprises applying the first polymer layer to the carrier and applying a second layer to the first polymer layer. The method of claim 10 , wherein the second layer is a copper layer.

12. The method of claim 10 or 11, wherein the first polymer layer and the second layer both comprise polydimethylsiloxane (PDMS).

13. The method of claim 12, wherein the first polymer layer comprises polydimethylsiloxane (PDMS) doped with nanoparticles configured to generate heat when the nanoparticles are exposed to magnetic induction heating or infrared light exposure.

14. The method of claim 10, wherein the carrier is configured as an electrostatic chuck, the electrostatic chuck comprises an electrode embedded in the carrier, and the interface layer comprises a semiconductive polymer film, and further comprising: inducing an electrostatic attraction force between the carrier and the interface layer before forming the one or more redistribution layers.

15. A method for processing a semiconductor substrate, comprising: applying a non-stick interface layer to a dielectric carrier, wherein the interface layer comprises a first polymer layer and a second layer; forming one or more redistribution layers on the second layer; separating the second layer from the dielectric carrier via at least one of magnetic induction heating, infrared exposure, or electrostatic repulsion; and At least one of the first polymer layer and the second layer is removed from the one or more redistribution layers.

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