Semiconductor device

Patent metadata

Field	Value
Publication number	US-2016190232-A1
Application number	US-201615063733-A
Country	US
Kind code	A1
Filing date	Mar 8, 2016
Priority date	Dec 28, 2012
Publication date	Jun 30, 2016
Grant date	—

Abstract

A highly reliable semiconductor device including an oxide semiconductor is provided. Provided is a semiconductor device including an oxide semiconductor layer, an insulating layer in contact with the oxide semiconductor layer, a gate electrode layer overlapping with the oxide semiconductor layer, and a source electrode layer and a drain electrode layer electrically connected to the oxide semiconductor layer. The oxide semiconductor layer includes a first region having a crystal whose size is less than or equal to 10 nm and a second region which overlaps with the insulating layer with the first region provided therebetween and which includes a crystal part whose c-axis is aligned in a direction parallel to a normal vector of the surface of the oxide semiconductor layer.

First claim

1 . (canceled)

2 . An oxide semiconductor film comprising a crystalline part,
wherein the crystalline part includes indium, zinc, and a metal element, wherein the metal element is selected from the group consisting of aluminum, titanium, gallium, yttrium, zirconium, lanthanum, cerium, neodymium, and hafnium, wherein the crystalline part further includes silicon, wherein a size of the crystalline part is less than or equal to 10 nm, and wherein a plurality of circumferentially distributed spots are observed in a measurement area greater than or equal to an area with a diameter of 5 nmφ and less than or equal to an area with a diameter of 10 nmφ in a nanobeam electron diffraction pattern of a cross-section of the oxide semiconductor film.

3 . The oxide semiconductor film according to claim 2 , wherein a halo pattern is observed in a selected-area electron diffraction pattern of a plane of the oxide semiconductor film.

4 . The oxide semiconductor film according to claim 2 ,
wherein, when zinc and oxygen are eliminated from consideration, a proportion of indium is greater than or equal to 25 atomic % and a proportion of the metal element is less than 75 atmic %.

5 . The oxide semiconductor film according to claim 2 , wherein a size of the crystalline part is less than or equal to 5 nm.

6 . The oxide semiconductor film according to claim 2 , further comprising an amorphous part.

7 . The oxide semiconductor film according to claim 2 ,
wherein the oxide semiconductor film comprises a first region including the crystalline part, and where the oxide semiconductor film further comprises a second region having a crystalline part whose c-axis is aligned in a direction parallel to a normal vector of a surface of the oxide semiconductor film.

8 . An oxide semiconductor film comprising a crystalline part,
wherein the crystalline part includes indium, zinc, and a metal element, wherein the metal element is selected from the group consisting of aluminum, titanium, gallium, yttrium, zirconium, lanthanum, cerium, neodymium, and hafnium, wherein the crystalline part further includes silicon, wherein concentration of silicon is lower than or equal to 3×10 18 /cm 3 , wherein a size of the crystalline part is less than or equal to 10 nm, and wherein a plurality of circumferentially distributed spots are observed in a measurement area greater than or equal to an area with a diameter of 5 nmφ and less than or equal to an area with a diameter of 10 nmφ in a nanobeam electron diffraction pattern of a cross-section of the oxide semiconductor film.

9 . The oxide semiconductor film according to claim 8 , wherein a halo pattern is observed in a selected-area electron diffraction pattern of a plane of the oxide semiconductor film.

10 . The oxide semiconductor film according to claim 8 ,
wherein, when zinc and oxygen are eliminated from consideration, a proportion of indium is greater than or equal to 25 atomic % and a proportion of the metal element is less than 75 atmic %.

11 . The oxide semiconductor film according to claim 8 , wherein a size of the crystalline part is less than or equal to 5 nm.

12 . The oxide semiconductor film according to claim 8 , further comprising an amorphous part.

13 . The oxide semiconductor film according to claim 8 ,
wherein the oxide semiconductor film comprises a first region including the crystalline part, and where the oxide semiconductor film further comprises a second region having a crystalline part whose c-axis is aligned in a direction parallel to a normal vector of a surface of the oxide semiconductor film.

14 . The oxide semiconductor film according to claim 8 , wherein the concentration of silicon is measured by secondary ion mass spectrometry.

Assignees

• Semiconductor Energy Lab

Inventors

• Yamazaki Shunpei
• Takahashi Masahiro
• Hirohashi Takuya
• Tsubuku Masashi
• Oota Masashi

Classifications

• H10D86/441

  Interconnections, e.g. scanning lines · CPC title

• H10D86/425

  having different crystal properties in different TFTs or within an individual TFT · CPC title

• H10D30/6755 Primary

  Oxide semiconductors, e.g. zinc oxide, copper aluminium oxide or cadmium stannate · CPC title

• H10D86/60 Primary

  wherein the TFTs are in active matrices · CPC title

• H10D62/405

  Orientations of crystalline planes · CPC title