Gas supply unit, substrate processing apparatus and supply gas setting method

Patent metadata

Field	Value
Publication number	US-9441791-B2
Application number	US-201213691125-A
Country	US
Kind code	B2
Filing date	Nov 30, 2012
Priority date	Dec 9, 2004
Publication date	Sep 13, 2016
Grant date	Sep 13, 2016

Abstract

A gas supply unit, for supplying a gas into a processing chamber in which a substrate is processed, includes a plurality of gas supply sources, a mixing line for mixing a plurality of gases supplied from the gas supply sources to make a gaseous mixture, a multiplicity of branch lines for branching the gaseous mixture to be supplied to a multiplicity of places in the processing chamber, and an additional gas supply unit for supplying a specified additional gas to a gaseous mixture flowing in at least one branch line. The gas supply unit also includes pressure gauges and valves for adjusting gas flow rates in the branch lines, respectively, and a pressure ratio controller for controlling that gaseous mixtures branched into the branch lines to have a specified pressure ratio by adjusting opening degrees of the valves based on measurement results obtained by using the pressure gauges.

First claim

What is claimed is:

1. An etching gas supply unit for supplying at least a first etching gases and a second etching gas to a processing chamber of a plasma etching apparatus, the etching gas supply unit comprising:
a plurality of first gas supply sources, each of which accommodates one of the first etching gases;
a second gas supply source accommodating the second etching gas;
a mixing portion to mix the first etching gases to make a gaseous mixture of the first etching gases;
a multiplicity of branch flow passages to branch the gaseous mixture and supply the branched gaseous mixtures;
a pressure control unit provided at each of the branch flow passages to adjust gas flow rates of the branched gaseous mixtures in the branch flow passages;
a second etching gas supply passage to supply the second etching gas to at least one of the branch flow passages to which the second etching gas supply passage is connected; and
a controller configured to control the following steps of:
supplying the gaseous mixture of the first etching gases to the branch flow passages via the mixing portion;
controlling a pressure ratio of the branched gaseous mixtures to be a specified pressure ratio by adjusting the pressure control units provided at the branch flow passages such that opening degrees of respective valves in the pressure control units are fixed under a condition in which the second etching gas is not supplied to any branch flow passage and, then, fixing the opening degrees of the valves;
supplying the second etching gas at a specified flow rate to said at least one of the branch flow passages to which the second etching gas supply passage is connected while the opening degrees of the valves remained fixed; and
injecting the first etching gases and the second etching gas toward the processing chamber.

2. The etching gas supply unit of claim 1 , wherein the second etching gas supply passage is connected to all the branch flow passages.

3. The etching gas supply unit of claim 1 , comprising a plurality of second gas supply sources.

4. An etching gas supply unit for supplying at least a first etching gases and a second etching gas to a processing chamber of a plasma etching apparatus, the etching gas supply unit comprising:
a plurality of first gas supply sources, each of which accommodates one of the first etching gases;
a second gas supply source accommodating the second etching gas;
a mixing portion to mix the first etching gases to make a gaseous mixture of the first etching gases;
a first branch flow passage to branch the gaseous mixture and supply a first gaseous mixture;
a second branch flow passage to branch the gaseous mixture and supply a second gaseous mixture;
a first pressure control unit provided at the first branch flow passage to adjust a gas flow rate of the first gaseous mixture in the first branch flow passage;
a second pressure control unit provided at the second branch flow passage to adjust a gas flow rate of the second gaseous mixture in the second branch flow passage;
a second etching gas supply passage to supply the second etching gas to at least one of the first branch flow passage and the second branch flow passage to which the second etching gas supply passage is connected; and
a controller configured to control the following steps of:
generating the gaseous mixture of the first etching gases;
branching the gaseous mixture of the first etching gases to supply the first gaseous mixture to the first branch flow passage and supply the second gaseous mixture to the second branch flow passage via the mixing portion;
controlling a pressure ratio of the first gaseous mixture to be a first pressure ratio and a pressure ratio of the second gaseous mixture to be a second pressure ratio by adjusting the first pressure control unit and the second pressure control unit such that opening degrees of respective valves in the first pressure control unit and the second pressure control unit are fixed under a condition in which the second etching gas is not supplied to any branch flow passage and, then, fixing the opening degrees of the valves;
supplying the second etching gas at a specified flow rate to said at least one of the first branch flow passage and the second branch flow passage to which the second etching gas supply passage is connected while the opening degrees of the valves remained fixed; and
injecting the first etching gases and the second etching gas toward the processing chamber.

5. A plasma etching apparatus for etching a substrate, the plasma etching apparatus comprising:
a processing chamber;
a gas introducing unit for introducing at least a first etching gases and a second etching gas into the processing chamber, the gas introducing unit including a plurality of buffer spaces;
an etching gas supply unit for supplying the first etching gases and the second etching gas to the buffer spaces; and
a plasma generating unit for generating a plasma of the first etching gases and the second etching gas in the processing chamber,
wherein the etching gas supply unit comprises:
a plurality of first gas supply sources, each of which accommodates one of the first etching gases;
a second gas supply source accommodating the second etching gas;
a mixing portion to mix the first etching gases to make a gaseous mixture of the first etching gases;
a multiplicity of branch flow passages to branch the gaseous mixture and supply the branched gaseous mixtures;
a pressure control unit provided at each of the branch flow passages to adjust gas flow rates of the branched gaseous mixtures in the branch flow passages;
a second etching gas supply passage to supply the second etching gas to at least one of the branch flow passages to which the second etching gas supply passage is connected; and
a controller configured to control the following steps of:
supplying the gaseous mixture of the first etching gases to the branch flow passages via the mixing portion;
controlling a pressure ratio of the branched gaseous mixtures to be a specified pressure ratio by adjusting the pressure control units provided at the branch flow passages such that opening degrees of respective valves in the pressure control units are fixed under a condition in which the second etching gas is not supplied to any branch flow passage and, then, fixing the opening degrees of the valves;
supplying the second etching gas at a specified flow rate to said at least one of the branch flow passages to which the second etching gas supply passage is connected while the opening degrees of the valves remained fixed; and
injecting the first etching gases and the second etching gas toward the processing chamber.

6. The plasma etching apparatus of claim 5 , wherein the second etching gas supply passage is connected to all the branch flow passages.

7. The plasma etching apparatus of claim 6 , the etching gas supply unit comprises a plurality of second gas supply sources.

8. The plasma etching apparatus of claim 5 , the etching gas supply unit comprises a plurality of second gas supply sources.

9. A gas supplying method using an etching gas supply unit for supplying at least a first etching gases and a second etching gas to a processing chamber of a plasma etching apparatus, the etching gas supply unit comprising:
a plurality of first gas supply sources, each of which accommodates one of the first etching gases;
a second gas supply source accommodating the second etching gas;
a mixing portion to mix the first etching gases to make a gaseous mixture of the first etching gases;
a multiplicity of branch flow passages to branch the gaseous mixture and supply the branched gaseous mixtures;
a pressure control unit provided at each of the branch flow

Assignees

• Tokyo Electron Ltd

Inventors

• Mizusawa Kenetsu
• Ito Keiki
• Itoh Masahide

Classifications

• H10P72/0604

  Process monitoring, e.g. flow or thickness monitoring · CPC title

• H10P72/0421

  for drying etching · CPC title

• Y10T137/2496

  Self-proportioning or correlating systems · CPC title

• Y10T137/87346

  Including mixing feature · CPC title

• C23C16/45512

  Premixing before introduction in the reaction chamber · CPC title