CENTROTHERM E1200 HT 260-3, Operating Instructions Manual

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E1200 HT 260-3
3BFunctional Description
23.04.07
4-24
00401010_41087
4.10.2 Process Flow LPCVD/PECVD
Each recipe predefines the process flow with the process parameters as for example
heating-up and cooling rates, process temperature, gas and gas flow velocity, dwell
time, etc. The following sequence gives an overview on a typical series of steps:
1. Furnace loading procedure: The process boat is loaded with wafers and moved
into the process tube with a paddle. The process boat is lowered. Then the paddle
is moved out of the process tube and the process tube is closed.
2. Evacuation: The entire gas is pumped out of the process tube.
3. N2 purging/evacuation cycles: A repeated purging/evacuation cycle is carried out.
The amount of cycles, time, nitrogen and the required pressure within the process
tube are stored in the recipe. The procedure ends with the evacuation. During this
time, the temperature in the process tube is regulated and set to setpoint
temperature.
4. Reaction phase: The process tube is flooded with process gases. Defined
temperature resp. plasma conditions are set and the desired reaction takes place
on the wafers. In the process, process gases are conducted into the process tube
for a defined amount of time. After passing through the process tube, the process
gases are lead into a waste gas system. From there they are led into the
customer's gas exhaust system (option).
5. N2 purging/evacuation cycles: A repeated purging/evacuation cycle is carried out.
The amount of cycles, time, nitrogen and the required pressure within the process
tube are defined in the recipe. The procedure ends with the N2 purging.
6. Furnace unloading procedure: The loading machine moves the paddle into the
process tube and lifts the process boat which is loaded with wafers. The paddle is
moved out of the process tube. The lift (option) takes the process boat with the
wafers and puts it into the storage (option) to cool down.