Devices and methods for electrochemical liquid phase epitaxy

Patent metadata

Field	Value
Publication number	US-10538860-B2
Application number	US-201815865432-A
Country	US
Kind code	B2
Filing date	Jan 9, 2018
Priority date	Jan 9, 2017
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

Electrochemical liquid phase epitaxy (ec-LPE) processes and devices are provided that can form precipitated epitaxial crystalline films or layers on a substrate. The precipitated films may comprise a semiconductor, such as germanium, silicon, or carbon. Dissolution into, saturation within, and precipitation of the semiconductor from a liquid metal electrode (e.g., Hg pool) near an interface region with a substrate yields a polycrystalline semiconductor material deposited as an epitaxial film. Reactor cells for use in an electrochemical liquid phase epitaxy (ec-LPE) device are also provided that include porous membranes to facilitate formation of the precipitated epitaxial crystalline films.

First claim

What is claimed is:

1. A reactor cell for an electrochemical liquid phase epitaxy (ec-LPE) device, the reactor cell comprising:
a substrate;
a liquid metal electrode adjacent to the substrate, wherein an interface region is defined between the substrate and the liquid metal electrode;
a porous membrane disposed on a side of the liquid metal electrode opposite from the substrate; and
a liquid electrolyte source disposed adjacent to and in fluid communication with the porous membrane, the source comprising a liquid electrolyte that comprises an oxide compound of a semiconductor element; wherein the substrate, liquid metal electrode, and porous membrane are compressed together under pressure, wherein a thickness of the liquid metal electrode is less than an effective pathlength of the semiconductor element in the liquid metal electrode and the reactor cell is configured in a presence of an electric potential to form an epitaxial planar layer of precipitated semiconductor element on the substrate at the interface region.

2. The reactor cell of claim 1 , wherein the thickness of the liquid metal electrode is less than or equal to about 300 micrometers.

3. The reactor cell of claim 1 , wherein the porous membrane comprises silicon carbide (SiC).

4. The reactor cell of claim 1 , wherein the porous membrane has an average surface pore size of greater than or equal to about 150 nm and less than or equal to about 250 nm.

5. The reactor cell of claim 1 , wherein the substrate is crystalline and the epitaxial layer is also crystalline.

6. The reactor cell of claim 1 , further comprising at least one port in fluid communication with a liquid metal delivery system that delivers liquid metal to the liquid metal electrode.

7. The reactor cell of claim 1 , wherein the porous membrane has edge regions that are hydrophobic and a central region that is hydrophilic to permit fluid communication between the liquid electrolyte and the liquid metal electrode.

8. The reactor cell of claim 1 , further comprising a plate disposed between the porous membrane and the substrate, wherein the plate comprises one or more open regions that define the liquid metal electrode.

9. The reactor cell of claim 1 , wherein the semiconductor element is selected from the group consisting of silicon, germanium, carbon, and combinations thereof.

Assignees

• Univ Michigan Regents

Inventors

• Maldonado Stephen
• Demuth Joshua
• Fahrenkrug Eli

Classifications

• H10P14/3411

  Silicon, silicon germanium or germanium · CPC title

• H10P14/265

  using solutions · CPC title

• H10P14/26

  using liquid deposition · CPC title

• H10D64/01338

  with a treatment, e.g. annealing, after the formation of the conductor · CPC title

• C30B19/12 Primary

  characterised by the substrate · CPC title