Thin film transistor and manufacturing method thereof, display substrate and display device

• US 9,773,917 B2
• Filed: 10/30/2014
• Issued: 09/26/2017
• Est. Priority Date: 05/07/2014
• Status: Active Grant

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: BOE Technology Group Co., Ltd.
• Inventors: Chen, Jiangbo, Wang, Dongfang
• Primary Examiner(s): Sarkar, Asok K
• Assistant Examiner(s): Anya, Igwe U
• Application Number:
  US14/651,376
• Publication Number:
  US 20160260834A1
• Time in Patent Office: 1,062 Days
• Field of Search: 257 43, 438104
• CPC Class Codes: C23C 14/08 Oxides C23C14/10 takes precedence
• CPC Class Codes: C23C 14/086 of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: C23C 14/14 Metallic material, boron or silicon
• CPC Class Codes: C23C 14/28 by wave energy or particle radiation C23C14/32 - C23C14/48 take precedence
• CPC Class Codes: C23C 14/3457 using other particles than noble gas ions C23C14/0036, C23C14/46 take precedence
• CPC Class Codes: C23C 14/3492 Variation of parameters during sputtering
• CPC Class Codes: C23C 16/345 Silicon nitride
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/02472 Oxides
• CPC Class Codes: H01L 21/02483 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02554 Oxides
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 29/045 by their particular orientation of crystalline planes
• CPC Class Codes: H01L 29/24 including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22 including organic materials H10K99/00
• 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 29/786 : Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785
• CPC Class Codes: H01L 29/7869 : having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
• CPC Class Codes: H01L 29/78696 : characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621

Abstract

A thin film transistor and a manufacturing method thereof, a display substrate and a display device are provided. The method of manufacturing the thin film transistor comprises forming an active layer (4) having characteristics of crystal orientation of C-axis on a substrate (1) by using indium gallium zinc oxide (InGaO₃(ZnO)_m), where m≧2. The active layer fabricated with InGaO₃(ZnO)_m has a good electron mobility, and the quality of the fabricated active layer is improved.

Claims

1. A method of manufacturing a thin film transistor, comprising:

forming an active layer having characteristics of crystal orientation of C-axis on a substrate by using indium gallium zinc oxide (InGaO₃(ZnO)_m), where m≧

2,

wherein the active layer is formed by depositing the indium gallium zinc oxide layer at least two times on the substrate,

wherein in a procedure of manufacturing the active layer having characteristics of crystal orientation of C-axis by using the indium gallium zinc oxide, depositing a first indium gallium zinc oxide layer with C axis crystal orientation via a physical vapor deposition process under a first power and a first speed, and depositing a second indium gallium zinc oxide layer on the formed first indium gallium zinc oxide layer via a physical vapor deposition process under a second power and a second speed, wherein the first indium gallium zinc oxide layer and the second indium gallium zinc oxide layer forms the active layer, and

wherein the first power is smaller than the second power, and the first speed is smaller than the second speed.

2. The method of manufacturing the thin film transistor according to claim 1, wherein both the first indium gallium zinc oxide layer and the second indium gallium zinc oxide layer are formed at a temperature of 200°

C.-400°

C.

3. The method of manufacturing the thin film transistor according to claim 2, wherein the active layer is formed in vacuum by using a Nd:

YAG laser; and

the laser has an output wavelength of 193-1064 nm, a repetition frequency larger than 1 Hz, and a pulse width less than 10 ns.

4. The method of manufacturing the thin film transistor according to claim 3, wherein the first power is a power before the laser focuses, which is 0.2-0.4 W.

5. The method of manufacturing the thin film transistor according to claim 2, wherein the active layer is formed in vacuum by using a Nd:

YAG laser, and

wherein the laser has an output wavelength of 1064 nm, a repetition frequency of 10 Hz, and a pulse width of 10 ns.

6. The method of manufacturing the thin film transistor according to claim 3, wherein the first power is a power before the laser focuses, which is 0.3 W.

7. The method of manufacturing the thin film transistor according to claim 1, wherein the first indium gallium zinc oxide layer is deposited for 10-30 s, and the formed first indium gallium zinc oxide layer has a thickness larger than 0 and less than or equal to 10 nm.

8. The method of manufacturing the thin film transistor according to claim 7, wherein the second power is a power before the laser focuses, which is 0.5-1.0 W.

9. The method of manufacturing the thin film transistor according to claim 7, wherein the second power is a power before the laser focuses, which is 0.5 W.

10. The method of manufacturing the thin film transistor according to claim 1, wherein the first indium gallium zinc oxide layer and the second indium gallium zinc oxide layer are formed by using a sputtering process under a condition of vacuum.

11. The method of manufacturing the thin film transistor according to claim 10, wherein when the sputtering is performed under the condition of vacuum, a mixture of oxygen gas and argon gas are input into a vacuum chamber.

12. The method of manufacturing the thin film transistor according to claim 11, wherein a ratio of oxygen gas and argon gas is 1:

4.

13. The method of manufacturing the thin film transistor according to claim 12, wherein the first indium gallium zinc oxide layer is formed by one scanning under a condition that the first power is 2-3 KW and a flow of oxygen is 25 standard ml/min;

and

the second indium gallium zinc oxide layer is formed by one scanning under a condition that the second power is 4-6 KW and a flow of oxygen is 25 standard ml/min.

14. The method of manufacturing the thin film transistor according to claim 12, wherein the first indium gallium zinc oxide layer is formed by one scanning under a condition that the first power is 3 KW and a flow of oxygen is 25 standard ml/min;

and

the second indium gallium zinc oxide layer is formed by one scanning under a condition that the second power is 4.5 KW and a flow of oxygen is 25 standard ml/min.

15. The method of manufacturing the thin film transistor according to claim 1, wherein the indium gallium zinc oxide (InGaO₃(ZnO)_m) comprises any one of InGaZn₂O₅, InGaZn₃O₆, InGaZn₄O₇, InGaZn₅O₈ or InGaZn₆O₉.

16. The method of manufacturing the thin film transistor according to claim 1, wherein the active layer is divided into three layers deposited on the substrate, wherein the growth speed of each of indium gallium zinc oxide layers is incrementally increased.