US 2013/0233401 A1 · N-CHANNEL FLOW RATIO CONTROLLER CALIBRATION

Abstract

Embodiments of the present invention generally relate to methods of controlling gas flow in etching chambers. The methods generally include splitting a single process gas supply source into multiple inputs of separate process chambers, such that each chamber processes substrates under uniform processing conditions. The method generally includes using a mass flow controller as a reference for calibrating a flow ratio controller. A span correction factor may be determined to account for the difference between the actual flow and the measured flow through the flow ratio controller. The span correction factors may be used to determine corrected set points for each channel of the flow controller using equations provided herein. Furthermore, the set points of the flow ratio controller may be made gas-independent using additional equations provided herein.

Claims17

Dependent claims

A method of calibrating a flow ratio controller for a tandem chamber having two process chambers, each process chamber having a gas diffuser comprising multiple gas zones disposed therein, each gas zone of each gas diffuser coupled to the same process gas supply, comprising:

a) setting all channels of a flow ratio controller coupled to the process gas supply to a set point allowing a maximum gas passage;
b) opening the downstream isolation valve of a first channel;
c) closing all downstream isolation valves for the remaining channels of the flow ratio controller;
d) setting the flow of a mass flow controller equal to the full scale flow of the first channel of the flow ratio controller;
e) stabilizing the flow of a process gas through the flow ratio controller;
f) calculating a span correction factor for the flow of the process gas through the first channel of the flow ratio controller;
g) repeating steps (b)-(f) for all other channels and calculating a span correction factor for the flow of the process gas through the remaining channels of the flow ratio controller;
and
h) determining the corrected set point for each channel of the flow ratio controller.

6 more elements

Dependencies are inferred from the claim text.

N-channel flow ratio controller calibration

Life of this patent

N-channel flow ratio controller calibration

Life of this patent

Abstract

Claims17