Chemical vapor deposition method for fabricating two-dimensional materials

Patent metadata

Field	Value
Publication number	US-10062568-B2
Application number	US-201715587551-A
Country	US
Kind code	B2
Filing date	May 5, 2017
Priority date	May 13, 2016
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

A method of synthesis of two-dimensional metal chalcogenide monolayers, such as WSe 2 and MoSe 2 , is based on a chemical vapor deposition approach that uses H 2 Se or alkyl or aryl selenide precursors to form a reactive gas. The gaseous selenium precursor may be introduced into a tube furnace containing a metal precursor at a selected temperature, wherein the selenium and metal precursors react to form metal chalcogenide monolayers.

First claim

What is claimed is:

1. A method of synthesizing a metal chalcogenide nanosheet comprising:
placing a solid metal precursor in a receptacle;
placing the solid-metal precursor-containing receptacle in a reaction chamber;
transmitting a gaseous selenium precursor through the reaction chamber;
reacting the gaseous selenium precursor with the metal precursor; and
forming the metal chalcogenide nanosheet on a substrate, the substrate being independent of the receptacle.

2. The method of claim 1 , wherein the metal chalcogenide nanosheet is selected from the group consisting of: WSe 2 ; MoSe 2 ; NbSe 2 ; PtSe 2 ; ReSe 2 ; TaSe 2 ; TiSe 2 ; ZrSe 2 ; ScSe 2 ; VSe 2 ; GaSe; Ga 2 Se 3 ; Bi 2 Se 3 ; GeSe; InSe; In 2 Se 3 ; SnSe 2 ; SnSe; SbSe 3 ; ZrSe 3 ; MnIn 2 Se 4 ; MgIn 2 Se 4 ; Pb 2 Bi 2 Se 5 ; SnPSe 3 ; and PdPSe; and alloys and doped derivatives thereof.

3. The method of claim 1 , wherein the metal precursor is selected from the group consisting of: a metal; a metal diselenide bulk powder; a metal oxide; an inorganic precursor; an organometallic precursor; a metal alkyl precursor; an ethylhexanoate salt; and bis(ethylbenzene)molybdenum.

4. The method of claim 1 , wherein the gaseous selenium precursor is selected from the group consisting of: H 2 Se; an alkyl selenide; and an aryl selenide.

5. The method of claim 1 , further comprising reacting the gaseous selenium precursor with the metal precursor in the presence of a reducing gas.

6. The method of claim 1 , further comprising reacting the gaseous selenium precursor with the metal precursor in the presence of H 2 S.

7. The method of claim 1 , wherein the gaseous selenium precursor is mixed with a ligand.

8. The method of claim 7 , wherein the ligand is selected from the group consisting of: an alkane thiol; an alkane selenol; and a combination of an alkane thiol and an alkane selenol.

9. The method of claim 1 , wherein the reaction chamber is a chemical vapor deposition reactor.

10. The method of claim 1 , further comprising reacting the gaseous selenium precursor and the metal precursor at a temperature, or a range of temperatures, between 100° C. and 550° C.

11. The method of claim 1 , further comprising reacting the gaseous selenium precursor and the metal precursor at a temperature, or a range of temperatures, above 550° C.

12. The method of claim 1 , further comprising reacting the gaseous selenium precursor and the metal precursor in the presence of an inert carrier gas.

13. The method of claim 1 , wherein the nanosheet has lateral dimensions less than 10 nm.

14. The method of claim 1 , wherein the nanosheet has lateral dimensions between 10 nm and 100 μm.

15. The method of claim 1 , wherein the nanosheet has lateral dimensions greater than 100 μm.

16. The method of claim 1 , wherein reacting the gaseous selenium precursor with the metal precursor is conducted at a pressure below atmospheric pressure.

17. The method of claim 1 , wherein reacting the gaseous selenium precursor with the metal precursor is conducted at atmospheric pressure.

18. The method of claim 1 , wherein reacting the gaseous selenium precursor with the metal precursor is conducted at a pressure above atmospheric pressure.

Assignees

• Nanoco Technologies Ltd

Inventors

• Pickett Nigel
• Masala Ombretta
• Savjani Nicky Prabhudas

Classifications

• H10P14/24

  using chemical vapour deposition [CVD] · CPC title

• H10P14/3436 Primary

  being chalcogenide semiconductor materials not being oxides, e.g. ternary compounds · CPC title

• C23C16/46

  characterised by the method used for heating the substrate (C23C16/48, C23C16/50 take precedence) · CPC title

• C23C16/305

  Sulfides, selenides, or tellurides · CPC title

• C23C16/4481

  by evaporation using carrier gas in contact with the source material (C23C16/4486 takes precedence) · CPC title