The electrical contact properties of Co/4H-SiC structures are investigated. A carbon interfacial layer between a Co film and SiC is used to improve the Ohmic contact properties significantly. The C film is deposited prior to Co film deposition on SiC using DC sputtering. The high quality Ohmic contact and specific contact resistivity of 2.30 x 10<'-6>Ω.cm<'2> are obtained for Co/C/SiC structures after two-step annealing at 500 ℃ for 10 min and 1050 ℃ for 3 min. The physical properties of the contacts are examined by using XRD. The results indicate that the Co-based metal contacts have better structural stability of silicide phases formed after the high temperature annealing and carbon-enriched layer is produced below the contact, playing a key role in forming an Ohmic contact through the reduction of effective Schottky barrier height for the transport of electrons. The thermal stability of Au/Co/C/SiC Ohmic contacts is investigated. The contacts remain Ohmic on doped n-type (2.8 x 10<'18> cm<'-3>) 4H-SiC after thermal aging treatment at 500 ℃ for 20 h.
参考文献
[1] | Kazuhiro 1,Toshitake O,Hidehisa T.Simultaneous formation of Ni/Al Ohmic contacts to both n-and p-type 4H-SiC.J Electron Mater,2008,37(11):1647 |
[2] | Han R,Yang Y T,Wang P.Ohmic contact properties of multimetal films on n-type 4H-SiC.Chinese Journal of Semiconductors,2007,28(2):149 |
[3] | Sang Y H,Ki H K,Jong K K.Ohmic contact formation mechanism of Ni on n-type 4H-SiC.Appl Phys Lett,2001,79(12):1816 |
[4] | Lu W,Mitchel W C,Landis G R.Ohmic constants on p-type silicon carbide using carbon films.United States Patent,No.6747291B1,2004 |
[5] | Yang S J,Kim C K,Noh I H.Study of Co-and Ni-based Ohmic contacts to n-type 4H-SiC.Diamond and Related Materials,2004,13(8):1149 |
[6] | Lu W,Mitchel W C,Landis G R,et al.Ohmic contact properties of Ni/C film on 4H-SiC.Solid-State Electron,2003,47:2001 |
[7] | Chen W,Xu H,Kian P L.Structure of Co deposited 6HSiC(0001).Surf Sci,2005,596(5):107 |
[8] | Park S W,Kim Y I,Kwak J S.Investigation of Co/SiC interface reaction.J Electron Mater,1997,26(3):172 |
[9] | Hang W,Chen Z Z,Chen B Y,et al.Effect of hydrofluoric acid etching time on Ni/6H-SiC contacts.Chin Plays Soe,2009,58(5):3443 |
[10] | Lu W,Mitehel W C,Thornton C A,et al.Carbon structural transitions and Ohmic contacts on 4H-SiC.J Electron Mater,2003,32(5):426 |
[11] | Lu W,Mitchel W C,Landis G R.Electrical contact behavior of Ni/C60/4H-SiC structures.Journal of Vacuum Science & Technology,2003,21:1510 |
[12] | Lu W,Mitchel W C,Landis G R,et al.Catalytic graphitization and Ohmic contact formation on 4H-SiC.Appl Phys,2003,93(9):5397 |
[13] | Ariel V,Lisa M P,Dorothy L.Investigation of thermal stability and degradation mechanisms m Ni-based Ohmic contacts to n-type SiC for high-temperature gas sensors.J Electron Mater,2009,38(4):569 |
[14] | Kuchuk A V,Guziewicz M,Ratajezak R,et al.Long-term stability of Ni-silicide Ohmic contact to n-type 4H-SiC.Microelectron Eng,2008,4:11 |
- 下载量()
- 访问量()
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%