Sputtering target, oxide semiconductor film and semiconductor device

• US 8,668,849 B2
• Filed: 05/10/2012
• Issued: 03/11/2014
• Est. Priority Date: 03/20/2007
• Status: Active Grant

• Current Assignee: Idemitsu Kosan Company Limited
• Original Assignee: Idemitsu Kosan Company Limited
• Inventors: Inoue, Kazuyoshi, Yano, Koki, Kasami, Masashi
• Primary Examiner(s): KOPEC, MARK T
• Application Number:
  US13/468,119
• Publication Number:
  US 20120273777A1
• Time in Patent Office: 670 Days
• Field of Search: 252/518.1, 252/519.51, 252/520.1, 252/521.2, 257/43
• US Class Current: 252/518.1
• CPC Class Codes: C04B 2235/3201 Alkali metal oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3203 Lithium oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3206 Magnesium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3217 Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
• CPC Class Codes: C04B 2235/3224 Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
• CPC Class Codes: C04B 2235/3225 Yttrium oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3229 Cerium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3232 Titanium oxides or titanates, e.g. rutile or anatase
• CPC Class Codes: C04B 2235/3244 Zirconium oxides, zirconates, hafnium oxides, hafnates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3251 Niobium oxides, niobates, tantalum oxides, tantalates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3275 Cobalt oxides, cobaltates or cobaltites or oxide forming salts thereof, e.g. bismuth cobaltate, zinc cobaltite
• CPC Class Codes: C04B 2235/3279 Nickel oxides, nickalates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3281 Copper oxides, cuprates or oxide-forming salts thereof, e.g. CuO or Cu2O
• CPC Class Codes: C04B 2235/3284 Zinc oxides, zincates, cadmium oxides, cadmiates, mercury oxides, mercurates or oxide forming salts thereof
• CPC Class Codes: C04B 2235/3286 Gallium oxides, gallates, indium oxides, indates, thallium oxides, thallates or oxide forming salts thereof, e.g. zinc gallate
• CPC Class Codes: C04B 2235/3287 Germanium oxides, germanates or oxide forming salts thereof, e.g. copper germanate
• CPC Class Codes: C04B 2235/3409 Boron oxide, borates, boric acids, or oxide forming salts thereof, e.g. borax
• CPC Class Codes: C04B 2235/72 Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics
• CPC Class Codes: C04B 2235/77 Density
• CPC Class Codes: C04B 2235/81 Materials characterised by the absence of phases other than the main phase, i.e. single phase materials
• CPC Class Codes: C04B 35/01 : based on oxide ceramics
• CPC Class Codes: C23C 14/086 : of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: C23C 14/3414 : Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
• CPC Class Codes: H01L 29/66969 : of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• CPC Class Codes: H01L 29/7869 : having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

A sputtering target including an oxide sintered body, the oxide sintered body containing indium (In) and at least one element selected from gadolinium (Gd), dysprosium (Dy), holmium (Ho), erbium (Er) and ytterbium (Yb), and the oxide sintered body substantially being of a bixbyite structure.

Claims

1. A semiconductor device using a crystalline oxide comprising indium as a semiconductor, wherein the crystalline oxide has an electron career concentration of less than 10¹⁸ /cm³,

wherein the crystalline oxide comprises a positive trivalent element other than indium and the crystalline oxide is a polycrystalline oxide.

2. The semiconductor device according to claim 1, wherein the crystalline oxide is a nondegenerate semiconductor.

3. The semiconductor device according to claim 1, wherein the crystalline oxide comprises a positive divalent element.

4. The semiconductor device according to claim 3, wherein the positive divalent element is at least one element of Zn, Mg, Ni, Co and Cu.

5. The semiconductor device according to claim 3, wherein the atomic ratio of the number of the atoms of the positive divalent element ([M2]) to the number of the atoms of total metal elements contained in the crystalline oxide ([A]) is 0.001≦

[M2]/[A]<

0.2.

6. The semiconductor device according to claim 5, wherein the electron mobility to the electron carrier concentration of the crystalline oxide logarithmically proportionally increases by at least changing the atomic ratio of [M2] to [A].

7. The semiconductor device according to claim 1, wherein the positive trivalent element is at least one element of B, Al, Ga, Sc, Y and a lanthanoid element.

8. The semiconductor device according to claim 1, wherein the atomic ratio of the number of the atoms of the positive trivalent element ([M3]) to the number of the atoms of total metal elements contained in the crystalline oxide ([A]) is 0.001≦

[M3]/[A]<

0.2.

9. The semiconductor device according to claim 8, wherein the electron mobility to the electron carrier concentration of the crystalline oxide logarithmically proportionally increases by at least changing the atomic ratio of [M3] to [A].

10. The semiconductor device according to claim 1, wherein the crystalline oxide has a PAN resistance.

11. The semiconductor device according to claim 1, wherein the concentration of Li and Na contained in the crystalline oxide is 1000 ppm or less.

12. The semiconductor device according to claim 1, wherein the crystalline oxide is used as a channel layer in a field-effect transistor.

13. The semiconductor device according to claim 1, wherein the semiconductor is obtained by subjecting a sputtering target to sputtering, wherein said sputtering target is formed of an oxide sintered body comprising indium (In) and at least one element selected from gadolinium (Gd), dysprosium (Dy), holmium (Ho), erbium (Er) and ytterbium (Yb), and the oxide sintered body is substantially of a bixbyite structure.

14. The semiconductor device according to claim 13, wherein said oxide sintered body has an atomic ratio represented by M/(In +M) of 0.01 to 0.25, wherein M is the content of gadolinium (Gd), dysprosium (Dy), holmium (Ho), erbium (Er) and ytterbium (Yb).

15. The semiconductor device according to claim 13, wherein the sputtering target further comprises a positive divalent metal element and the content of the positive divalent metal element to the total amount of metal elements contained in the sputtering target is 1 to 10 at %.

16. The semiconductor device according to claim 15, wherein the positive divalent metal element is zinc (Zn) and/or magnesium (Mg).

17. The semiconductor device according to claim 13, wherein the sputtering target further comprises a metal element with an atomic valency of positive tetravalency or higher, wherein the content of the metal element with an atomic valency of positive tetravalency or higher to the total metal elements contained in the sputtering target is 100 ppm to 2000 ppm in atomic ratio.

18. The semiconductor device according to claim 17, wherein the metal element with an atomic valency of positive tetravalency or higher metal element is at least one element selected from germanium (Ge), titanium (Ti), zirconium (Zr), niobium (Nb) and cerium (Ce).