A backside release process for compound semiconductors

Abstract

The present invention relates to the field of semiconductor processing technology, and specifically to a back-side detachment process for compound semiconductors. The present invention comprises S1 permanently bonding the back sides of multiple compound semiconductor substrates to a high-temperature resistant carrier through a carbon deposition reaction, thereby completing a wafer process for the front sides of the compound semiconductor substrates; S2 using a transparent organic film to fill gaps in the compound semiconductor substrates, completing front-side planarization, and then temporarily bonding the front sides of the compound semiconductor substrates to a glass carrier; S3 penetrating the glass carrier and the transparent organic film through a laser to break the carbon bonds between the compound semiconductor substrates and the high-temperature resistant carrier, and between the compound semiconductor substrates and the compound semiconductor substrates; the present invention bonds the back sides of the compound semiconductor substrates to the high-temperature resistant substrate through a carbon deposition reaction, and then breaks the bonded carbon through a laser, thereby directly separating the compound semiconductor substrates from the high-temperature resistant substrate, which is convenient and quick, and improves the separation efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor processing, in particular to a backside release process of a compound semiconductor. Background Art

[0002] Semiconductor materials can be divided into two categories: elemental semiconductors and compound semiconductors. The former are semiconductors formed by materials such as silicon (Si) and germanium (Ge), while the latter are formed by compounds such as gallium arsenide (GaAs), gallium nitride (GaN), and silicon carbide (SiC). Semiconductors have undergone three major generations of evolution. Gallium arsenide (GaAs), gallium nitride (GaN), and silicon carbide (SiC) semiconductors represent the second and third generations of semiconductors, respectively. Compared to the first generation of semiconductors, they offer significantly superior high-frequency and high-temperature performance, but are more expensive to manufacture, making them the new leaders in the semiconductor industry.

[0003] Currently, during the processing of compound semiconductors, the back of the wafer is permanently bonded to a silicon-based carrier. The silicon-based carrier is then ground down to the bonding layer, and then completely removed by etching. This grinding process is relatively delicate, requires high process requirements, and is time-consuming, which has a certain impact on industrial production. Summary of the Invention

[0004] The object of the present invention is to provide a backside release process for compound semiconductors to solve the problems raised in the above background technology.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A backside release process for a compound semiconductor comprises the following steps:

[0007] S1. Permanently bonding the back sides of multiple compound semiconductor substrates to a high-temperature resistant carrier through a carbon deposition reaction to complete the wafer process of the front sides of the compound semiconductor substrates;

[0008] S2, filling the gaps in the compound semiconductor substrate with a transparent organic film to complete the front surface planarization, and then temporarily bonding the front surface of the compound semiconductor substrate to a glass carrier;

[0009] S3, penetrating the glass carrier and the transparent organic film with a laser to break the carbon bonds between the compound semiconductor substrate and the high-temperature resistant carrier and between the compound semiconductor substrates;

[0010] S4. Flip the glass carrier and remove the high-temperature resistant carrier. After completing the wafer process on the back side of the compound semiconductor substrate, perform laser debonding, remove the glass carrier, clean and remove the adhesive layer, and complete the compound semiconductor element.

[0011] Furthermore, the compound semiconductor substrate includes a gallium arsenide substrate, a gallium nitride substrate and a silicon carbide substrate;

[0012] The high temperature resistant carrier plate is made of ceramic or graphite;

[0013] The transparent organic film is a thick film elastic composite tape or a polyimide film.

[0014] Furthermore, the S1 is specifically:

[0015] S1.1. The surface of the high-temperature resistant carrier is provided with a plurality of adsorption holes. The back side of the compound semiconductor substrate is placed on the high-temperature resistant carrier with the plurality of adsorption holes for adsorption;

[0016] S1.2. Using a carbon deposition reaction, a carbon deposition layer is formed on the surface of the compound semiconductor substrate, and the back surface of the compound semiconductor substrate is bonded to a high-temperature resistant carrier;

[0017] S1.3, coating the sidewalls of the compound semiconductor substrate with photoresist, and then etching the carbon on the surface of the compound semiconductor substrate with a laser;

[0018] S1.4. Complete the wafer process on the front side of the compound semiconductor substrate.

[0019] Furthermore, the front wafer process includes a yellow light process, an ILD process, a metal process and an etching process.

[0020] Furthermore, the back wafer process in step S4 includes a yellow light process, a particle implantation process and a metal process.

[0021] Beneficial effects of the present invention:

[0022] 1. The present invention bonds the back surface of the compound semiconductor substrate to the high-temperature resistant substrate through a carbon deposition reaction, and then breaks the bonded carbon through laser, thereby directly separating the compound semiconductor substrate from the high-temperature resistant substrate. This is convenient and fast, and improves the separation efficiency.

[0023] 2. After completing the wafer process on the front side of the compound semiconductor substrate, the present invention uses an organic film to fill the gaps in the compound semiconductor substrate to complete the front side flattening, overcome the height difference between multiple compound semiconductor substrates, and fill the gaps to form a stress buffer. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0025] Figure 1 Schematic diagram of the molding structure of step S1 of the present invention;

[0026] Figure 2 Schematic diagram of the molding structure of step S2 of the present invention;

[0027] Figure 3 Schematic diagram of the molding structure of step S3 of the present invention;

[0028] Figure 4 This is a molding flow chart of step S1 of the present invention;

[0029] Figure 5 It is a molding flow chart from step S2 to step S3 of the present invention;

[0030] Figure 6 It is a molding flow chart of step S4 of the present invention.

[0031] The reference numerals in the figures are as follows:

[0032] 1. High-temperature resistant carrier; 11. Adsorption holes; 2. Compound semiconductor substrate; 3. Carbon deposition layer; 4. Transparent organic film; 5. Glass carrier. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0034] Example 1

[0035] Reference Figure 1-3 As shown, a backside release process of a compound semiconductor includes the following steps:

[0036] S1. Permanently bonding the back sides of multiple compound semiconductor substrates to a ceramic carrier through a carbon deposition reaction to complete the wafer manufacturing process for the front sides of the compound semiconductor substrates. Specifically,

[0037] S1.1. The surface of the ceramic carrier is provided with a plurality of adsorption holes. The back side of the compound semiconductor substrate is placed on the ceramic carrier with the plurality of adsorption holes for adsorption;

[0038] S1.2. Using a carbon deposition reaction, a carbon deposition layer is formed on the surface of the compound semiconductor substrate, and the back surface of the compound semiconductor substrate is bonded to a ceramic carrier.

[0039] S1.3, coating the sidewalls of the compound semiconductor substrate with photoresist, and then etching the carbon on the surface of the compound semiconductor substrate with a laser;

[0040] S1.4. Complete the wafer process on the front side of the compound semiconductor substrate.

[0041] The front wafer process includes:

[0042] The front wafer process includes yellow light process, ILD process, metal process and etching process.

[0043] S2, using a thick film elastic composite tape to fill the gaps in the compound semiconductor substrate, completing the front surface planarization, and then temporarily bonding the front surface of the compound semiconductor substrate to the glass carrier;

[0044] S3, penetrating the glass carrier and the thick-film elastic composite tape with a laser to break the carbon bonds between the compound semiconductor substrate and the ceramic carrier and between the compound semiconductor substrates;

[0045] S4. Flip the glass carrier and remove the ceramic carrier. After completing the wafer process on the back side of the compound semiconductor substrate, perform laser debonding, remove the glass carrier, clean and remove the adhesive layer, and complete the compound semiconductor device.

[0046] Among them, the back wafer process includes yellow light process, particle implantation process and metal process.

[0047] Example 2

[0048] A backside release process for a compound semiconductor comprises the following steps:

[0049] S1. Permanently bonding the back sides of multiple compound semiconductor substrates to a graphite carrier through a carbon deposition reaction to complete the wafer manufacturing process for the front sides of the compound semiconductor substrates, which is specifically as follows:

[0050] S1.1. The surface of the graphite carrier is provided with a plurality of adsorption holes. The back side of the compound semiconductor substrate is placed on the graphite carrier with the plurality of adsorption holes for adsorption;

[0051] S1.2. Using a carbon deposition reaction, a carbon deposition layer is formed on the surface of the compound semiconductor substrate, and the back surface of the compound semiconductor substrate is bonded to a graphite carrier;

[0052] S1.3, coating the sidewalls of the compound semiconductor substrate with photoresist, and then etching the carbon on the surface of the compound semiconductor substrate with a laser;

[0053] S1.4. Complete the wafer process on the front side of the compound semiconductor substrate.

[0054] The front wafer process includes:

[0055] The front wafer process includes yellow light process, ILD process, metal process and etching process.

[0056] S2, using a polyimide film to fill the gaps in the compound semiconductor substrate to complete the front surface planarization, and then temporarily bonding the front surface of the compound semiconductor substrate to a glass carrier;

[0057] S3, penetrating the glass carrier and the polyimide film with a laser to break the carbon bonds between the compound semiconductor substrate and the graphite carrier and between the compound semiconductor substrates;

[0058] S4. Flip the glass carrier and remove the graphite carrier. After completing the wafer process on the back side of the compound semiconductor substrate, perform laser debonding, remove the glass carrier, clean and remove the adhesive layer, and complete the compound semiconductor device.

[0059] Among them, the back wafer process includes yellow light process, particle implantation process and metal process.

[0060] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and modifications fall within the scope of the invention as claimed.

Claims

1. A backside release process for a compound semiconductor, characterized in that: The following steps are involved: S1. Permanently bonding the back sides of multiple compound semiconductor substrates to a high-temperature resistant carrier through a carbon deposition reaction to complete the wafer process of the front sides of the compound semiconductor substrates; S2, filling the gaps in the compound semiconductor substrate with a transparent organic film to complete the front planarization, and then temporarily bonding the front of the compound semiconductor substrate to a glass carrier; S3, penetrating the glass carrier and the transparent organic film with a laser to break the carbon bonds between the compound semiconductor substrate and the high-temperature resistant carrier and between the compound semiconductor substrates; S4, flipping the glass carrier, removing the high-temperature resistant carrier, completing the back wafer process of the compound semiconductor substrate, performing laser debonding, removing the glass carrier, cleaning and removing the adhesive layer, and completing the compound semiconductor device; The compound semiconductor substrate includes a gallium arsenide substrate, a gallium nitride substrate and a silicon carbide substrate; The high temperature resistant carrier plate is made of ceramic or graphite; The transparent organic film is a thick film elastic composite tape or a polyimide film; The S1 is specifically: S1.

1. The surface of the high-temperature resistant carrier is provided with a plurality of adsorption holes. The back side of the compound semiconductor substrate is placed on the high-temperature resistant carrier with the plurality of adsorption holes for adsorption; S1.

2. Using a carbon deposition reaction, a carbon deposition layer is formed on the surface of the compound semiconductor substrate, and the back surface of the compound semiconductor substrate is bonded to a high-temperature resistant carrier; S1.3, coating the sidewalls of the compound semiconductor substrate with photoresist, and then etching the carbon on the surface of the compound semiconductor substrate with a laser; S1.

4. Complete the wafer process on the front side of the compound semiconductor substrate.

2. The backside release process of a compound semiconductor according to claim 1, characterized in that: The front wafer process includes a yellow light process, an ILD process, a metal process and an etching process.

3. The backside release process of a compound semiconductor according to claim 1, characterized in that: The back wafer process in step S4 includes a yellow light process, a particle implantation process and a metal process.

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