Method for forming semiconductor device

Patent metadata

Field	Value
Publication number	US-10381380-B2
Application number	US-201815947853-A
Country	US
Kind code	B2
Filing date	Apr 8, 2018
Priority date	Aug 28, 2015
Publication date	Aug 13, 2019
Grant date	Aug 13, 2019

Abstract

The present invention provides a method of forming a semiconductor device. First, a substrate having a first insulating layer formed thereon is provided. After forming an oxide semiconductor layer on the first insulating layer, two source/drain regions are formed on the oxide semiconductor layer. A bottom oxide layer is formed to entirely cover the source/drain regions, following by forming a high-k dielectric layer on the bottom oxide layer. Next, a thermal process is performed on the high-k dielectric layer, and a plasma treatment is performed on the high-k dielectric layer in the presence of a gas containing an oxygen element.

First claim

What is claimed is:

1. A method for forming a semiconductor device, comprising:
providing a substrate having a first insulating layer formed thereon;
forming an oxide semiconductor layer on the first insulating layer;
forming two source/drain regions on the oxide semiconductor layer, sidewalls of the two source/drain regions being vertical aligned with sidewalls of the oxide semiconductor layer respectively;
forming a bottom oxide layer simultaneously covering the sidewalls of the source/drain regions and the sidewalls of the oxide semiconductor layer;
forming a high-k dielectric layer on the bottom oxide layer; and
performing an oxygen treatment on the high-k dielectric layer in the presence of a gas containing an oxygen element.

2. The method for forming a semiconductor device according to claim 1 , further comprising:
forming a second insulating layer between the oxide semiconductor layer and the source/drain regions, wherein the second insulating layer comprises an oxide semiconductor material different from the oxide semiconductor layer.

3. The method for forming a semiconductor device according to claim 2 , wherein the second insulating layer and the oxide semiconductor layer comprise indium gallium zinc oxide (InGaZnO), InGaO 2 InZnO 2 , GaInO, ZnInO, or GaZnO.

4. The method for forming a semiconductor device according to claim 1 , further comprising:
forming a top oxide layer on the high-k dielectric layer, wherein the bottom oxide layer, the high-k dielectric layer and the top oxide layer comprises a sandwiched gate dielectric structure; and
forming a first gate electrode between the source/drain regions and on the sandwiched gate dielectric structure, wherein the first gate electrode is vertically aligned with the top oxide layer and the high-k dielectric layer.

5. The method for forming a semiconductor device according to claim 4 , wherein a sidewall of the top oxide layer and a sidewall of high-k dielectric layer are vertically aligned with a sidewall of the first gate electrode.

6. The method for forming a semiconductor device according to claim 5 , wherein the forming of the sandwiched gate dielectric structure and the first gate electrode comprises:
sequentially forming a high-k dielectric material layer and an oxide layer covered on the bottom oxide layer;
forming a gate layer on the oxide layer; and
simultaneously patterning the high-k dielectric material layer, the oxide layer and the gate layer, to form the first gate electrode, the high-k dielectric layer and the top oxide layer.

7. The method for forming a semiconductor device according to claim 4 , further comprising:
forming a second gate electrode below the oxide semiconductor layer, wherein the second gate electrode overlaps the oxide semiconductor layer.

8. The method for forming a semiconductor device according to claim 1 , wherein the oxygen treatment is performed by supplying 100% O 2 gas under 400° C.

9. The method for forming a semiconductor device according to claim 1 , further comprising:
forming a first contact structure electrically connected to the source/drain regions.

10. The method for forming a semiconductor device according to claim 9 , further comprising:
forming a second contact structure electrically connected to the first gate electrode.

11. The method for forming a semiconductor device according to claim 10 , wherein the bottom oxide layer directly contacts the source/drain regions.

Assignees

• United Microelectronics Corp

Inventors

• Hsu Chia-Fu
• Wu Chun-Yuan

Classifications

• H10P14/6519

  the substance being oxygen · CPC title

• H10P14/3434

  being oxide semiconductor materials (Group IIB-VIA semiconductor materials H10P14/3424) · CPC title

• H10P14/60

  of insulating materials · CPC title

• H10D64/011

  of electrodes ohmically coupled to a semiconductor · CPC title

• H10W20/069

  by forming self-aligned vias or self-aligned contact plugs · CPC title