Preparation method of a germanium-based schottky junction

Patent metadata

Field	Value
Publication number	US-9484208-B2
Application number	US-201314380026-A
Country	US
Kind code	B2
Filing date	Sep 30, 2013
Priority date	Mar 18, 2013
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

The present invention discloses a preparation method of a germanium-based Schottky junction, comprising, cleaning a surface of N-type germanium-based substrate, then depositing a layer of CeO 2 on the surface, and further depositing a layer of metal. The stability Ce—O—Ge bonds can be formed at the interface after rare earth oxides CeO 2 are in contact with the germanium substrate, and this is beneficial to reduce the interface state density, improve the quality of the interface, and reduce the MIGS and suppress Fermi-level pinning. Meanwhile, the tunneling resistance introduced by CeO 2 between the metal and the germanium substrate is smaller relative to the case of Si 3 N 4 , Al 2 O 3 , Ge 3 N 4 or the like. In view of the excellent surface characteristics and small conduction band offset relative to the germanium substrate, interposing of the CeO 2 dielectric layer is applicable to the preparation the germanium-based Schottky junction having a low resistivity.

First claim

What is claimed is:

1. A preparation method of a germanium-based Schottky junction, comprising, cleaning a surface of a N-type germanium-based substrate, then depositing a layer of passivation material CeO 2 on the surface, and further depositing a layer of metal,
wherein the N-type germanium-based substrate, the layer of passivation material CeO 2 , and the layer of metal form a Schottky junction.

2. The preparation method according to claim 1 , wherein, the depositing of the layer of passivation material CeO 2 is performed by ALD, PLD, MBE, or CVD process.

3. The preparation method according to claim 1 , wherein, the layer of passivation material CeO 2 is deposited to have a thickness of 0.3˜2 nm.

4. The preparation method according to claim 1 , wherein, the deposited metal is Al, Pt, Au, Ti, Ni, TiN, TaN, or W.

5. The preparation method according to claim 1 , wherein, performing Photolithography process, etching process, and annealing process after depositing the metal.

6. The preparation method according to claim 1 , wherein, the N-type germanium substrate is a bulk germanium substrate, a Germanium-on-Insulator substrate, or any substrate containing germanium epitaxial layer on a surface thereof.

7. The preparation method according to claim 1 , wherein, the N-type germanium substrate is a germanium-containing compound semiconductor substrate.

8. The preparation method according to claim 7 , wherein, the germanium-containing compound is SiGe or GeSn.

Assignees

• Univ Beijing

Inventors

• Huang Ru
• Lin Meng
• Li Zhiqiang
• An Xia
• Li Ming
• Yun Quanxin
• Li Min
• Liu Pengqiang
• Zhang Xing

Classifications

• H10P70/15

  by wet cleaning only (H10P70/52 takes precedence) · CPC title

• H10P50/00

  Etching of wafers, substrates or parts of devices · CPC title

• H10P14/69396

  the material containing at least one rare earth metal element, e.g. oxides of lanthanides, scandium or yttrium · CPC title

• H10P14/6339

  deposition by cyclic CVD, e.g. ALD, ALE or pulsed CVD · CPC title

• H10P14/6334

  using decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition (deposition by physical ablation of a target H10P14/6329) · CPC title