Low-thermal-budget Au-free ohmic contact to an ultrathin barrier AlGaN/GaN heterostructure utilizing a micro-patterned ohmic recess

Wen Shi; Sen Huang; Xinhua Wang; Qimeng Jiang; Yixu Yao; Lan Bi; Yuchen Li; Kexin Deng; Jie Fan; Haibo Yin; Ke Wei; Yankui Li; Jingyuan Shi; Haojie Jiang; Junfeng Li; Xinyu Liu

doi:10.1088/1674-4926/42/9/092801

Journals >Journal of Semiconductors >Volume 42 >Issue 9 >Page 092801 > Article

Journal of Semiconductors
Vol. 42, Issue 9, 092801 (2021)

Low-thermal-budget Au-free ohmic contact to an ultrathin barrier AlGaN/GaN heterostructure utilizing a micro-patterned ohmic recess

Wen Shi^1、2, Sen Huang^1、2, Xinhua Wang^1、2, Qimeng Jiang^1、2, Yixu Yao^1、2, Lan Bi^1、2, Yuchen Li^1、2, Kexin Deng^1、2, Jie Fan^1、2, Haibo Yin^1、2, Ke Wei^1、2, Yankui Li^1、2, Jingyuan Shi^1、2, Haojie Jiang^1、2, Junfeng Li^1、2, and Xinyu Liu^1、2

Author Affiliations

¹Key Laboratory of Microelectronic Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, China

²Institute of Microelectronics, University of Chinese Academy of Sciences, Beijing 100049, China

show less

DOI: 10.1088/1674-4926/42/9/092801 Cite this Article

Wen Shi, Sen Huang, Xinhua Wang, Qimeng Jiang, Yixu Yao, Lan Bi, Yuchen Li, Kexin Deng, Jie Fan, Haibo Yin, Ke Wei, Yankui Li, Jingyuan Shi, Haojie Jiang, Junfeng Li, Xinyu Liu. Low-thermal-budget Au-free ohmic contact to an ultrathin barrier AlGaN/GaN heterostructure utilizing a micro-patterned ohmic recess[J]. Journal of Semiconductors, 2021, 42(9): 092801 Copy Citation Text

EndNote(RIS)

BibTex

Plain Text

show less

Fig. 1. (Color online) (a) Schematic cross section of the fabricated Si-CMOS-compatible GaN MIS-HEMTs utilizing a micro-patterned ohmic recess. (b) SEM image. (c) Line profile of the micro-patterned AlGaN/GaN heterostructure measured by atomic force microscopy (AFM).

Download full size | View in the Article

(a) Linear fit of the fabricated Ti/Al/Ti/TiN ohmic contact resistances versus TLM spacing. (b) Temperature-dependent characteristics: RC and RSH. (c) ρC as fitted by thermionic field emission model. (d) Temperature-dependent transfer length LT.

Fig. 2. (a) Linear fit of the fabricated Ti/Al/Ti/TiN ohmic contact resistances versus TLM spacing. (b) Temperature-dependent characteristics: R_C and R_SH. (c) ρ_C as fitted by thermionic field emission model. (d) Temperature-dependent transfer length L_T.

Download full size | View in the Article

Fig. 3. (Color online) (a) DC output, (b) transfer, and (c) off-state leakage characteristics of the fabricated CMOS-process compatible LPCVD-SiN_x/AlGaN/GaN MIS-HEMTs.

Download full size | View in the Article

AlGaN/GaN heterostructure	Ohmic metal stack	Annealing temperature (°C)	Recessed-AlGaN barrier thickness in the patterned region (nm)	Side length / Separation of pattern (μm)	L_T (μm)	R_C (Ω·mm)	R_SH (Ω/sq)
30 nm Al_0.25Ga_0.75N/GaN^[24]	TiSi₂/TiN	non-alloy	5	5.00/10.00	13.41	5.86	437
24 nm Al_0.3Ga_0.7N/GaN^[17]	Ti/Al/Ni/Au	850	15	0.50/0.50	0.35	0.12	341
2 nm GaN(cap)/18 nm Al_0.26Ga_0.74N/GaN^[18]	Ti/Al/Ni/Au	790	12	1.00/1.00	1.10	0.52	475
	Ti/Al/Ni/Au	810	12	1.00/1.00	1.00	0.48	475
	Ti/Al/Ni/Au	790	over-recess 30	1.00/1.00	1.06	0.51	475
	Ti/Al/Ni/Au	810	over-recess 30	1.00/1.00	1.06	0.50	475
(UTB) 1 nm GaN(cap)/ 3 nm Al_0.25Ga_0.75N/ 1 nm AlN/GaN^[16]	Ti/Al/Ti/TiN	600	5	/	4.33	1.57	363
(UTB) 1 nm GaN(cap)/ 4 nm Al_0.25Ga_0.75N/ 1 nm AlN/GaN (This work)	Ti/Al/Ti/TiN	550	over-recess ~1	1.50/1.50	1.45	0.56	385
	Ti/Al/Ti/TiN	550	over-recess ~10	1.50/1.50	1.45	0.58	399

Table 1. The summary of micro-patterned ohmic contacts to various AlGaN/GaN heterostructures.

Download Citation

Save the article for my favorites

Paper Information