Apparatus for electroless metal deposition having filter system and associated oxygen source

Patent metadata

Field	Value
Publication number	US-9752231-B2
Application number	US-201213469607-A
Country	US
Kind code	B2
Filing date	May 11, 2012
Priority date	May 11, 2012
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

One or more aspects of this invention pertain to fabrication of electronic devices. One aspect of the present invention is a system for electroless deposition of metal on a substrate. According to one or more embodiments of the present invention, the system comprises a main subsystem in combination with one or more subsystems for electroless deposition on a substrate. Another aspect of the present invention is a method of making an electronic device. According to one or more embodiments of the present invention, the method comprises one or more processes. Descriptions according to one or more embodiments of the system and the processes are presented.

First claim

What is claimed is:

1. A system for electroless deposition of metal on a substrate comprising:
an electroless deposition chamber to hold the substrate for electroless deposition;
a reservoir to hold an electroless deposition solution; said electroless deposition solution has a dissolved oxygen concentration and is configured for electroless deposition of metal;
an input line between the electroless deposition chamber and the reservoir to provide the electroless deposition solution from the reservoir to the electroless deposition chamber;
a filter coupled into the input line to remove particles from the electroless deposition solution before the electroless depositon solution enters the electroless deposition chamber;
a reclaim line between the electroless deposition chamber and the reservoir to recycle electroless deposition solution from the electroless deposition chamber back to the reservoir;
a filter system coupled into the reclaim line so as to filter the electroless deposition solution to remove particles of metal, the filter system located directly in the reclaim line between the electroless deposition chamber and the reservoir; said filter system consisting essentially of filter element, a first vavle connected between the electroless deposition chamber and the filter element, a second valve connected between the reservoir and the filter element, and a third valve connected between the filter element and the first valve; and a connection to an oxygen source to provide dissolved oxygen to the reclaim line through the third valve, wherein the dissolved oxygen is directly supplied to the reclaim line leading into the filter element and the third valve is configured to produce a higher dissolved oxygen concentration in the electroless deposition solution to dissolved metal particles trapped at the filter element.

2. The system of claim 1 , wherein the filter system has a U-shaped fluid conduit connecting the first valve, the second valve, and the third valve; the filter being disposed proximate the bottom of the U-shaped fluid conduit so as to trap liquid at the bottom of the U-shaped fluid conduit so as to wet the filter.

3. The system of claim 1 , wherein the connection to the oxygen source to provide dissolved oxygen to the reclaim line through the third valve comprises a connection to the filter system so as to provide the electroless deposition solution with the dissolved oxygen concentration higher than a level of the dissolved oxygen concentration in equilibrium with a gas mixture above the electroless deposition solution at one atmosphere pressure where said gas mixture is 0.5% oxygen gas.

4. The system of claim 1 , comprising:
a liquid sensor to detect the presence of liquid in the electroless deposition chamber, the liquid sensor disposed proximate the connection of the reclaim line to the electroless deposition chamber;
the filter system coupled into the reclaim line, the filter system comprising a filter element;
a pump coupled into the reclaim line so as to move liquids from the electroless deposition chamber through the reclaim line, the pump being disposed between the filter element and the liquid sensor;
the reclaim line being formed so as to trap liquid at the filter element;
the liquid sensor being connected with the pump so that pump operation stops when the liquid sensor stops detecting liquid in the electroless deposition chamber.

Assignees

• Li Shijian
• Lam Res Corp

Inventors

• Li Shijian

Classifications

• H10P14/46

  using a liquid · CPC title

• C23C18/1617 Primary

  Purification and regeneration of coating baths · CPC title

• C23C18/1683

  Control of electrolyte composition, e.g. measurement, adjustment (regeneration of bath C23C18/1617) · CPC title

• C23C18/31

  Coating with metals · CPC title

• C23C18/16 Primary

  by reduction or substitution, e.g. electroless plating (C23C18/54 takes precedence) · CPC title