Method for controlling N-type 4H-SiC homogenous epitaxial doping

[0025] Example 1

[0026] Step 1: Place the silicon carbide substrate in the reaction chamber of the silicon carbide CVD equipment.

[0027] (1.1) Selection bias A 4H silicon carbide substrate with a crystal orientation of 8° is placed in the reaction chamber of the silicon carbide CVD equipment;

[0028] (1.2) Vacuum the reaction chamber until the pressure in the reaction chamber is lower than 1×10 -7 mbar.

[0029] Step two, heating the reaction chamber in a hydrogen stream.

[0030] (2.1) Open the hydrogen switch leading to the reaction chamber and control the hydrogen flow to gradually increase to 80L / min;

[0031] (2.2) Turn on the vacuum pump to extract the gas in the reaction chamber and keep the pressure of the reaction chamber at 300mbar;

[0032] (2.3) Gradually increase the power of the heating source to slowly increase the temperature of the reaction chamber. When the temperature exceeds 1400°C, add C with a flow rate of 5 mL / min to the hydrogen stream. 3 H 8 .

[0033] Step

[0048] Example 2

[0049] Step 1. Select the bias The 4H silicon carbide substrate with crystal orientation 8° is placed in the reaction chamber of the silicon carbide CVD equipment; the reaction chamber is evacuated until the pressure in the reaction chamber is lower than 1×10 -7 mbar.

[0050] Step 2. Open the H leading to the reaction chamber 2 Switch to control the hydrogen flow to gradually increase to 80L / min, and at the same time turn on the vacuum pump to extract the gas in the reaction chamber, keep the pressure of the reaction chamber at 500mbar; gradually increase the power of the RF heating source, so that the temperature of the reaction chamber slowly rises, when the temperature of the reaction chamber After reaching 1400°C, add C at a flow rate of 7mL / min into the hydrogen stream 3 H 8 .

[0051] Step 3. After the temperature of the reaction chamber reaches 1580°C, keep the temperature of the reaction chamber constant, and keep the flow of H into the reaction chamber

[0055] Example 3

[0056] The first step is to select the bias The 4H silicon carbide substrate with crystal orientation 8° is placed in the reaction chamber of the silicon carbide CVD equipment; the reaction chamber is evacuated until the pressure in the reaction chamber is lower than 1×10 -7 mbar.

[0057] The second step is to open the H leading to the reaction chamber 2 Switch to control the hydrogen flow to gradually increase to 80L / min, and at the same time turn on the vacuum pump to extract the gas in the reaction chamber, keep the pressure of the reaction chamber at 700mbar; gradually increase the power of the RF heating source to slowly increase the temperature of the reaction chamber, when the temperature of the reaction chamber After reaching 1400°C, add C at a flow rate of 10mL / min into the hydrogen stream 3 H 8

[0058] In the third step, the substrate is etched in situ.

[0059] (3.1) When the temperature of the reaction chamber reaches 1600℃, keep the temperature of t