System And Method For Controllable Non-Volatile Metal Removal

Patent metadata

Field	Value
Publication number	US-2016265121-A1
Application number	US-201514657170-A
Country	US
Kind code	A1
Filing date	Mar 13, 2015
Priority date	Mar 13, 2015
Publication date	Sep 15, 2016
Grant date	—

Abstract

A system and method for removing metal from a substrate in a controlled manner is disclosed. The system includes a chamber, with one or more gas inlets to allow the flow of gasses into the chamber, at least one exhaust pump, to exhaust gasses from the chamber, and a heater, capable of modifying the temperature of the chamber. In some embodiments, one or more gasses are introduced into the chamber at a first temperature. The atoms in these gasses chemically react with the metal on the surface of the substrate to form a removable compound. The gasses are then exhausted from the chamber, leaving the removable compound on the surface of the substrate. The temperature of the chamber is then elevated to a second temperature, greater than the sublimation temperature of the removable compound. This increased temperature allows the removable compound to become gaseous and be exhausted from the chamber.

First claim

1 . A method of removing metal from a substrate, comprising:
introducing one or more processing gasses into a chamber at a first temperature, wherein a substrate is disposed in the chamber; chemically reacting the one or more processing gasses with metal disposed on the substrate to form a removable compound, where the removable compound sublimes at a known temperature, and wherein the first temperature is less than the known temperature; exhausting the one or more processing gasses from the chamber after the chemically reacting; increasing a temperature within the chamber to a second temperature, greater than the known temperature, after the exhausting, so that the removable compound becomes gaseous; and eliminating the gaseous removable compound from the chamber.

2 . The method of claim 1 , further comprising repeating the introducing, chemically reacting, exhausting, increasing and eliminating a plurality of times until a desired amount of metal is removed from the substrate.

3 . The method of claim 1 , wherein the metal comprises platinum.

4 . The method of claim 3 , wherein the one or more processing gasses comprise chlorine and carbon monoxide.

5 . The method of claim 4 , wherein the removable compound comprises chlorinated platinum carbonyl (Pt(CO) 2 Cl 2 ).

6 . A method of removing metal from a substrate, comprising:
introducing a first processing gas into a chamber where a substrate is disposed at a first temperature; chemically reacting the first processing gas with metal disposed on the substrate to form a precursor of a removable compound, where the removable compound sublimes at a known temperature, and wherein the first temperature is less than the known temperature; exhausting the first processing gas from the chamber after the chemically reacting; increasing a temperature within the chamber to a second temperature, greater than the known temperature, after the exhausting; introducing a second processing gas into the chamber after the exhausting, so that the second processing gas reacts with the precursor to form the removable compound, and wherein the removable compound becomes gaseous; and eliminating the gaseous removable compound from the chamber.

7 . The method of claim 6 , further comprising repeating the introducing the first processing gas, chemically reacting, exhausting, increasing, introducing the second processing gas and eliminating a plurality of times until a desired amount of metal is removed from the substrate.

8 . The method of claim 6 , wherein the metal comprises platinum.

9 . The method of claim 8 , wherein the first processing gas comprises chlorine and the second processing gas comprises carbon monoxide.

10 . The method of claim 9 , wherein the removable compound comprises chlorinated platinum carbonyl (Pt(CO) 2 Cl 2 ).

11 . The method of claim 9 , wherein the precursor comprises platinum chloride (PtCl 2 ).

12 . A workpiece processing system, comprising:
a chamber comprising a gas inlet and an exhaust port; a heating element in communication with the chamber; a gas storage container containing at least one processing gas; a valve disposed between the gas storage container and the gas inlet; an exhaust pump in communication with the exhaust port; and a controller, wherein the controller: actuates the valve to introduce the at least one processing gas into the chamber at a first temperature; actuates the valve to stop a flow of the at least one processing gas into the chamber; actuates the exhaust pump to exhaust the at least one processing gas from the chamber after a first dwell time; actuates the heating element to raise a temperature of the chamber to a second temperature after the at least one processing gas has been exhausted; and actuates the exhaust pump to eliminate a removable compound produced by a chemical reaction between the at least one processing gas and a metal disposed on a surface of a substrate disposed in the chamber.

13 . The workpiece processing system of claim 12 , wherein the at least one processing gas comprises chlorine and carbon monoxide.

14 . The workpiece processing system of claim 12 , wherein the at least one processing gas comprises chlorine and further comprising a second gas storage container, and a second valve disposed between the gas storage container and the gas inlet, wherein carbon monoxide is disposed in the second storage container.

15 . The workpiece processing system of claim 14 , wherein the controller:
actuates the second valve to introduce carbon monoxide into the chamber at the first temperature; and actuates the second valve to stop a flow of carbon monoxide into the chamber, prior to actuating the heating element.

16 . The workpiece processing system of claim 14 , wherein the controller:
actuates the second valve to introduce carbon monoxide into the chamber at the second temperature.

17 . The workpiece processing system of claim 12 , wherein the removable compound comprises chlorinated platinum carbonyl (Pt(CO) 2 Cl 2 ).

18 . The workpiece processing system of claim 12 , wherein the first temperature is less than a temperature at which the removable compound sublimes, and the second temperature is greater than the temperature at which the removable compound sublimes.

19 . The workpiece processing system of claim 12 , wherein the metal comprises platinum.

Assignees

• Varian Semiconductor Equipment Ass Inc

Inventors

• Chen Tsung-Liang
• Schmiege Benjamin
• Anthis Jeffrey W
• Gilchrist Glen

Classifications

• H10P72/0604

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

• H10P72/0602

  Temperature monitoring · CPC title

• B05B15/00

  Details of spraying plant or spraying apparatus not otherwise provided for; Accessories · CPC title

• C23C18/1295

  with after-treatment of the deposited inorganic material · CPC title

• C23F1/12 Primary

  Gaseous compositions · CPC title