Hydrogenated p-channel metal oxide semiconductor thin film transistors

Patent metadata

Field	Value
Publication number	US-2016133751-A1
Application number	US-201514863289-A
Country	US
Kind code	A1
Filing date	Sep 23, 2015
Priority date	Nov 12, 2014
Publication date	May 12, 2016
Grant date	—

Abstract

This disclosure provides p-type metal oxide semiconductor materials that display good thin film transistor (TFT) characteristics. Also provided are TFTs including channels that include p-type oxide semiconductors, and methods of fabrication. The p-type metal oxide films may be hydrogenated such that they have a hydrogen content of at least 10 18 atoms/cm 3 , and in some implementations, at least 10 20 atoms/cm 3 , or higher. Examples of hydrogenated p-type metal oxide films include hydrogenated tin (II)-based films and hydrogenated copper (I)-based films. The TFTs may be characterized by having one or more TFT characteristics such as high mobility, low subthreshold swing (s-value), and high on/off current ratio.

First claim

What is claimed is:

1 . A method, comprising:
providing a substrate; forming a p-type metal oxide semiconductor layer on the substrate; and annealing the p-type metal oxide semiconductor layer in a hydrogen (H 2 )-containing atmosphere to form a hydrogenated p-type metal oxide semiconductor layer.

2 . The method of claim 1 , wherein the hydrogenated p-type metal oxide semiconductor layer has a hydrogen concentration of at least 10 18 atoms/cm 3 .

3 . The method of claim 1 , wherein the p-type metal oxide semiconductor is a Sn (II)-based oxide semiconductor layer.

4 . The method of claim 1 , wherein the p-type metal oxide semiconductor is a Cu (I)-based oxide semiconductor layer.

5 . The method of claim 1 , wherein the p-type metal oxide semiconductor is one of a compound in a group consisting of doped or undoped Cu 2 O, CuO, SnO, NiO, PbO, Ag 2 O, Mn 3 O 4 , ZnRh 2 O 4 , SrCu 2 O 2 , CuWO 4 , and Ln-Ru—O compounds where Ln is any lanthanide except cerium (Ce).

6 . The method of claim 1 , wherein the p-type metal oxide semiconductor is selected from p-type copper delafossites of the formula CuMO 2 , where M is a metal.

7 . The method of claim 1 , wherein the p-type metal oxide semiconductor is an ABO 2 oxide characterized by a delafossite crystal structure.

8 . The method of claim 1 , wherein forming the hydrogenated p-type metal oxide semiconductor layer includes depositing the p-type metal oxide layer in a hydrogen (H 2 )-containing atmosphere.

9 . The method of claim 1 , further comprising forming a gate electrode and a gate dielectric, wherein the gate dielectric is between the p-type metal oxide semiconductor layer and the gate electrode.

10 . An apparatus comprising a thin film transistor (TFT), the TFT comprising:
a source electrode; a drain electrode; and a semiconductor channel connecting the source electrode and the drain electrode, the semiconductor channel including a hydrogenated p-type metal oxide semiconductor produced by the method of claim 1 , wherein the hydrogenated p-type metal oxide semiconductor has a hydrogen concentration of at least 10 18 atoms/cm 3 .

11 . The apparatus of claim 10 , wherein the hydrogenated p-type metal oxide semiconductor has a hydrogen concentration of at least 10 19 atoms/cm 3 .

12 . The apparatus of claim 10 , wherein the hydrogenated p-type metal oxide semiconductor has a hydrogen concentration of at least 10 20 atoms/cm 3 .

13 . The apparatus of claim 10 , wherein the hydrogenated p-type metal oxide semiconductor has a hydrogen concentration of at least 10 21 atoms/cm 3 .

14 . The apparatus of claim 10 , wherein at least 95% of the semiconductor channel is the p-type metal oxide semiconductor.

15 . The apparatus of claim 10 , wherein the p-type metal oxide semiconductor is a Sn(II)-based oxide semiconductor layer.

16 . The apparatus of claim 10 , wherein the p-type metal oxide semiconductor is a Cu(I)-based oxide semiconductor layer.

17 . The apparatus of claim 10 , wherein the p-type metal oxide semiconductor is one of a compound in a group consisting of doped or undoped Cu 2 O, CuO, SnO, NiO, PbO, Ag 2 O, Mn 3 O 4 , ZnRh 2 O 4 , SrCu 2 O 2 , CuWO 4 , and Ln-Ru—O compounds, where Ln is any lanthanide except cerium (Ce).

18 . The apparatus of claim 10 , wherein the p-type metal oxide semiconductor is selected from p-type copper delafossites of the formula CuMO 2 , where M is a metal.

19 . The apparatus of claim 18 , wherein M is a Group IIIA or IIIB metal.

20 . The apparatus of claim 10 , wherein the p-type metal oxide semiconductor is an ABO 2 oxide characterized by a delafossite crystal structure.

21 . The apparatus of claim 10 , wherein the TFT is characterized by two or more of the following: a saturation mobility of at least 1.0 cm 2 /V·s, a s-value of less than 10 V/decade, and a current on/off ratio of at least 1×10 4 .

22 . The apparatus of claim 10 , wherein the TFT is part of a complementary metal-oxide-semiconductor (CMOS) TFT device.

23 . The apparatus of claim 10 , wherein the TFT is a bottom gate TFT.

24 . The apparatus of claim 10 , wherein the TFT is a top gate TFT.

25 . The apparatus of claim 10 , further comprising: a display; a processor that is configured to communicate with the display, the processor being configured to process image data; and a memory device that is configured to communicate with the processor.

26 . The apparatus of claim 25 , further comprising: a driver circuit configured to send at least one signal to the display; and a controller configured to send at least a portion of the image data to the driver circuit.

27 . The apparatus of claim 26 , wherein the driver circuit includes the TFT.

28 . The apparatus of claim 25 , further comprising: an image source module configured to send the image data to the processor, wherein the image source module includes at least one of a receiver, transceiver, and transmitter.

29 . The apparatus of claim 25 , further comprising: an input device configured to receive input data and to communicate the input data to the processor.

Assignees

• Qualcomm Inc

Inventors

• Nomura Kenji

Classifications

• H10P14/38

  characterised by treatments done after the formation of the materials · CPC title

• H10D99/00

  Subject matter not provided for in other groups of this subclass · CPC title

• H10D84/85

  Complementary IGFETs, e.g. CMOS · CPC title

• H10D62/60

  Impurity distributions or concentrations · CPC title

• H10D62/40

  Crystalline structures · CPC title