Preparation method of sapphire-based vertical diode epitaxial wafer

Abstract

The invention relates to a preparation method of a sapphire-based vertical diode epitaxial wafer, and the method specifically comprises the following steps: providing a sapphire substrate, putting the sapphire substrate into a graphite plate of a reaction chamber, introducing ammonia gas into the reaction chamber, forming a plurality of grooves in a bearing surface of the sapphire substrate, and arranging the grooves at intervals; the groove is filled with an SIC material to form an SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially growing an epitaxial structure on the bearing surface of the sapphire substrate; and adjusting the rotating speed of the graphite disc by adopting at least one step type speed regulation until the rotating speed of the graphite disc meets the set rotating speed. The method has the advantages that the etching effect of hydrogen can be effectively avoided, so that the substrate is prevented from being warped greatly, the integrity and appearance quality of the epitaxial wafer are improved, the situation that a graphite disc is smashed due to flying of the epitaxial wafer is avoided, and the photoelectric property of the epitaxial wafer is also ensured.

Description

Technical Field

[0001] The present invention relates to a method for preparing a sapphire-based vertical diode epitaxial wafer. Background Art

[0002] Light Emitting Diode (LED), as a highly influential new product in the optoelectronic industry, has the characteristics of small size, long service life, rich and colorful colors, low energy consumption, etc., and is widely used in fields such as lighting, display screens, signal lights, backlights, toys, etc. The core structure of an LED is an epitaxial wafer, and the production of the epitaxial wafer has a greater impact on the optoelectronic properties of the LED. In related technologies, a GaN-based LED generally includes a sapphire substrate and an epitaxial structure stacked on the bearing surface of the sapphire substrate. The sapphire substrate is usually a patterned substrate, with protruding structures arranged at intervals on the bearing surface. The protruding structures can provide a stable growth space for the buffer layer of the epitaxial structure during the growth of the epitaxial structure, so as to improve the crystal quality of the epitaxial structure. However, there is a large lattice mismatch between the sapphire substrate and the GaN material, and when the thickness of the grown epitaxial structure is relatively thin, the edge region of the epitaxial structure is prone to uneven growth on the patterned sapphire substrate, and thus the crystal quality at the edge of the epitaxial structure is poor, affecting the quality of the LED.

[0003] How to provide a method for preparing a sapphire-based vertical diode epitaxial wafer has become a research direction. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for preparing a sapphire-based vertical diode epitaxial wafer to solve the problems raised in the above background art.

[0005] To solve the above technical problems, the technical solution provided by the present invention is: A method for preparing a sapphire-based vertical diode epitaxial wafer, specifically including the following steps:

[0006] Provide a sapphire substrate, place the sapphire substrate in a graphite tray in the reaction chamber, introduce ammonia gas into the reaction chamber, form a plurality of grooves on the bearing surface of the sapphire substrate, and the plurality of grooves are arranged at intervals; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite tray by using at least one stepwise speed adjustment until the rotation speed of the graphite tray meets the set rotation speed.

[0007] As a preferred solution, the stepwise speed adjustment includes a first stage, a second stage, a third stage, and a fourth stage that are executed in sequence.

[0008] As a preferred solution, in the first stage, control the rotation speed of the graphite tray to increase.

[0009] As a preferred solution, during the second stage, the rotation speed of the graphite disk is controlled to decrease.

[0010] As a preferred solution, during the third stage, the rotation speed of the graphite disk is controlled to increase.

[0011] As a preferred solution, during the fourth stage, the rotation speed of the graphite disk is controlled to remain unchanged. In the same stepwise speed regulation, the maximum rotation speed of the graphite disk in the first stage is less than the maximum rotation speed of the graphite disk in the third stage; an epitaxial layer is grown on the substrate.

[0012] The advantages of the present invention are as follows: Ammonia flowing to the substrate through the gas flow can play a role in stabilizing the substrate; replacing hydrogen with ammonia can effectively avoid the etching effect of hydrogen, thereby preventing large warping of the substrate. It can greatly improve the problem that the substrate is prone to warping during the process of growing the epitaxial layer, resulting in the flying of the epitaxial wafer, improve the integrity and appearance quality of the epitaxial wafer, avoid the situation where the epitaxial wafer flies and damages the graphite disk, and also ensure the optoelectronic performance of the epitaxial wafer. Specific Embodiments

[0013] The following uses specific embodiments to illustrate the present invention, which is not a limitation of the present invention.

[0014] Embodiment 1

[0015] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0016] Provide a sapphire substrate, place the sapphire substrate in the graphite disk of the reaction chamber, introduce ammonia into the reaction chamber, form a plurality of grooves on the bearing surface of the sapphire substrate, and the plurality of grooves are arranged at intervals; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite disk by using at least one stepwise speed regulation until the rotation speed of the graphite disk meets the set rotation speed.

[0017] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are sequentially executed.

[0018] As a preferred solution of this embodiment, during the first stage, the rotation speed of the graphite disk is controlled to increase.

[0019] As a preferred solution of this embodiment, during the second stage, the rotation speed of the graphite disk is controlled to decrease.

[0020] As a preferred solution of this embodiment, during the third stage, the rotation speed of the graphite disk is controlled to increase.

[0021] As a preferred solution of this embodiment, in the fourth stage, the rotation speed of the graphite disk is controlled to be constant. In the same stepwise speed regulation, the maximum rotation speed of the graphite disk in the first stage is less than the maximum rotation speed of the graphite disk in the third stage; an epitaxial layer is grown on the substrate.

[0022] Example 2

[0023] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0024] Provide a sapphire substrate, place the sapphire substrate in a graphite disk in a reaction chamber, introduce ammonia gas into the reaction chamber, form a plurality of grooves on the bearing surface of the sapphire substrate, and the plurality of grooves are arranged at intervals; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite disk by using at least one stepwise speed regulation until the rotation speed of the graphite disk meets the set rotation speed.

[0025] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are sequentially executed.

[0026] Example 3

[0027] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0028] Provide a sapphire substrate, place the sapphire substrate in a graphite disk in a reaction chamber, introduce ammonia gas into the reaction chamber, form a plurality of grooves on the bearing surface of the sapphire substrate, and the plurality of grooves are arranged at intervals; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite disk by using at least one stepwise speed regulation until the rotation speed of the graphite disk meets the set rotation speed.

[0029] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are sequentially executed.

[0030] As a preferred solution of this embodiment, in the first stage, the rotation speed of the graphite disk is controlled to increase.

[0031] Example 4

[0032] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0033] Provide a sapphire substrate, place the sapphire substrate in a graphite tray in a reaction chamber, introduce ammonia gas into the reaction chamber, form a plurality of grooves on the bearing surface of the sapphire substrate, and arrange the plurality of grooves at intervals; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite tray by using at least one stepwise speed regulation until the rotation speed of the graphite tray meets the set rotation speed.

[0034] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are executed in sequence.

[0035] As a preferred solution of this embodiment, in the first stage, control the rotation speed of the graphite tray to increase.

[0036] As a preferred solution of this embodiment, in the second stage, control the rotation speed of the graphite tray to decrease.

[0037] Example 5

[0038] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0039] Provide a sapphire substrate, place the sapphire substrate in a graphite tray in a reaction chamber, introduce ammonia gas into the reaction chamber, form a plurality of grooves on the bearing surface of the sapphire substrate, and arrange the plurality of grooves at intervals; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite tray by using at least one stepwise speed regulation until the rotation speed of the graphite tray meets the set rotation speed.

[0040] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are executed in sequence.

[0041] As a preferred solution of this embodiment, in the first stage, control the rotation speed of the graphite tray to increase.

[0042] As a preferred solution of this embodiment, in the second stage, control the rotation speed of the graphite tray to decrease.

[0043] As a preferred solution of this embodiment, in the third stage, control the rotation speed of the graphite tray to increase.

[0044] Example 6

[0045] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0046] Provide a sapphire substrate, place the sapphire substrate in a graphite tray in a reaction chamber, introduce ammonia gas into the reaction chamber, form a plurality of grooves on the bearing surface of the sapphire substrate, and arrange the plurality of grooves at intervals; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite tray by at least one stepwise speed regulation until the rotation speed of the graphite tray meets the set rotation speed.

[0047] Example 7

[0048] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0049] Provide a sapphire substrate, place the sapphire substrate in a graphite tray in a reaction chamber, introduce ammonia gas into the reaction chamber, and form a plurality of grooves on the bearing surface of the sapphire substrate; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite tray by at least one stepwise speed regulation until the rotation speed of the graphite tray meets the set rotation speed.

[0050] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are executed in sequence.

[0051] As a preferred solution of this embodiment, in the first stage, control the rotation speed of the graphite tray to increase.

[0052] As a preferred solution of this embodiment, in the second stage, control the rotation speed of the graphite tray to decrease.

[0053] As a preferred solution of this embodiment, in the third stage, control the rotation speed of the graphite tray to increase.

[0054] As a preferred solution of this embodiment, in the fourth stage, control the rotation speed of the graphite tray to remain unchanged. In the same stepwise speed regulation, the maximum rotation speed of the graphite tray in the first stage is less than the maximum rotation speed of the graphite tray in the third stage; grow an epitaxial layer on the substrate.

[0055] Example 8

[0056] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0057] Provide a sapphire substrate, place the sapphire substrate in a graphite tray in a reaction chamber, introduce ammonia gas into the reaction chamber, and form a plurality of grooves on the bearing surface of the sapphire substrate; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite tray by at least one stepwise speed regulation until the rotation speed of the graphite tray meets the set rotation speed.

[0058] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are executed in sequence.

[0059] Example 9

[0060] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0061] Provide a sapphire substrate, place the sapphire substrate in a graphite tray in a reaction chamber, introduce ammonia gas into the reaction chamber, and form a plurality of grooves on the bearing surface of the sapphire substrate; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite tray by at least one stepwise speed regulation until the rotation speed of the graphite tray meets the set rotation speed.

[0062] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are executed in sequence.

[0063] As a preferred solution of this embodiment, in the first stage, control the rotation speed of the graphite tray to increase.

[0064] Example 10

[0065] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0066] Provide a sapphire substrate, place the sapphire substrate in a graphite tray in a reaction chamber, introduce ammonia gas into the reaction chamber, and form a plurality of grooves on the bearing surface of the sapphire substrate; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite tray by at least one stepwise speed regulation until the rotation speed of the graphite tray meets the set rotation speed.

[0067] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are executed in sequence.

[0068] As a preferred solution of this embodiment, in the first stage, the rotation speed of the graphite disk is controlled to increase.

[0069] As a preferred solution of this embodiment, in the second stage, the rotation speed of the graphite disk is controlled to decrease.

[0070] Embodiment 11

[0071] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0072] Provide a sapphire substrate, place the sapphire substrate in the graphite disk of the reaction chamber, introduce ammonia into the reaction chamber, and form a plurality of grooves on the bearing surface of the sapphire substrate; fill the grooves with SIC material to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite disk by using at least one stepwise speed regulation until the rotation speed of the graphite disk meets the set rotation speed.

[0073] As a preferred solution of this embodiment, the stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are executed in sequence.

[0074] As a preferred solution of this embodiment, in the first stage, the rotation speed of the graphite disk is controlled to increase.

[0075] As a preferred solution of this embodiment, in the second stage, the rotation speed of the graphite disk is controlled to decrease.

[0076] As a preferred solution of this embodiment, in the third stage, the rotation speed of the graphite disk is controlled to increase.

[0077] Embodiment 12

[0078] A method for preparing a sapphire-based vertical diode epitaxial wafer specifically includes the following steps:

[0079] Provide a sapphire substrate, place the sapphire substrate in the graphite disk of the reaction chamber, introduce ammonia into the reaction chamber, and form a plurality of grooves on the bearing surface of the sapphire substrate; fill the grooves with SIC material to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite disk by using at least one stepwise speed regulation until the rotation speed of the graphite disk meets the set rotation speed.

[0080] The above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a sapphire-based vertical diode epitaxial wafer, characterized in that, Specifically, the following steps are included: Provide a sapphire substrate, place the sapphire substrate in a graphite tray in the reaction chamber, introduce ammonia gas into the reaction chamber, form a plurality of grooves on the bearing surface of the sapphire substrate, and arrange the plurality of grooves at intervals; fill SIC material in the grooves to form a SIC material layer, and the surface of the SIC material layer is flush with the bearing surface of the sapphire substrate; epitaxially grow an epitaxial structure on the bearing surface of the sapphire substrate; adjust the rotation speed of the graphite tray by using at least one stepwise speed regulation until the rotation speed of the graphite tray meets the set rotation speed.

2. The preparation method of the sapphire-based vertical diode epitaxial wafer according to claim 1, wherein: The stepwise speed regulation includes a first stage, a second stage, a third stage, and a fourth stage that are sequentially executed.

3. The preparation method of the sapphire-based vertical diode epitaxial wafer according to claim 2, characterized in that: In the first stage, control the rotation speed of the graphite tray to increase.

4. The method for preparing a sapphire-based vertical diode epitaxial wafer according to claim 2, characterized in that: In the second stage, control the rotation speed of the graphite tray to decrease.

5. The method for preparing a sapphire-based vertical diode epitaxial wafer according to claim 2, wherein: In the third stage, control the rotation speed of the graphite tray to increase.

6. The method for preparing a sapphire-based vertical diode epitaxial wafer according to claim 2, characterized in that: In the fourth stage, control the rotation speed of the graphite tray to remain unchanged. In the same stepwise speed regulation, the maximum rotation speed of the graphite tray in the first stage is less than the maximum rotation speed of the graphite tray in the third stage; grow an epitaxial layer on the substrate.