Delivery of liquid precursors to semiconductor processing reactors

• US 20040040505A1
• Filed: 09/03/2003
• Published: 03/04/2004
• Est. Priority Date: 09/25/1999
• Status: Abandoned Application

• Current Assignee: John Macneil
• Original Assignee: John Macneil
• Inventors: MacNeil, John
• Application Number:
  US10/653,153
• Publication Number:
  US 20040040505A1
• Time in Patent Office: Days
• US Class Current: 118/715
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: F04B 19/04 Pumps for special use
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/31612 on a silicon body
• CPC Class Codes: Y02E 60/34 Hydrogen distribution

Abstract

This invention relates to methods and apparatus for delivering liquid precursors to semi-conductor processing apparatus. The liquid precursor delivery system is generally indicated at 10 and includes a source 11, an inlet tube 12, a two-way valve 13, a pump assembly 14, an outlet tube 15, a shut-off valve 16 and a flash evaporator 17. The pump assembly 14 is in the form of a syringe or variable volume pump and is controlled by a combination of a step motor 27 and a linear encoder 30. The arrangement is such that unused liquid precursor can be returned to the source.

Claims

1. Apparatus for delivering a liquid precursor to a semiconductor processing reactor including a source for the liquid precursor, a volume calibrated positive displacement pump for drawing liquid precursor from the source via an input path and for delivering along an output path a known volume of liquid precursor to the reactor.

2. Apparatus as claimed in claim 1 further including a valve for connecting the pump to the input path or the output path.

3. Apparatus as claimed in claim 2 further including control means for controlling the pump and valve whereby the pump draws liquid in, whilst the reactor is not processing with this precursor.

4. Apparatus as claimed in claim 2 or claim 3 further including control means for controlling the pump and the valve whereby the pump returns some or all of the undelivered precursor to the source.

5. Apparatus as claimed in any one of the preceding claims wherein the pump is a syringe pump.

6. Apparatus as claimed in any of the preceding claims wherein the source includes a bottle or reservoir of liquid precursor.

7. Apparatus as claimed in claim 6 wherein the source includes at least two bottles or reservoirs and means for automatically connecting one bottle or reservoir to the inlet path as the other becomes empty.

8. A method of delivering a liquid precursor to a semiconductor processing reactor including:

(i) Drawing a liquid precursor along an input path, into a volume calibrated positive displacement pump from a source of liquid precursor; and

(ii) Delivering, along an output path, a known volume of liquid precursor.

9. A method as claimed in claim 8 including alternately connecting the pump to the input path and the output path.

10. A method as claimed in claim 8 or claim 9 wherein is after each volume delivery the pump returns some or all of the remaining liquid to the source, before drawing a fresh charge.