本篇論文中，目的是為探討1200V ,2 Amp 接面位障蕭基二極體 (Junction Barrier Schottky, JBS) 元件設計與製程。光罩設計與模擬方面，針對不同的P型離子佈植間距2-4 μm作調變，利於找出元件順向電壓降與反向漏電流此兩平衡(Trade-off)之關係。
我們嘗試找出不同蕭基金屬經適當熱處理後對於蕭基能障變化，根據最後結果套用於JBS元件上；倘若元件需操作於高壓下，蕭基能障高度將會是重要關鍵，經實驗證明能障高度確實能以金屬快速熱退火製程的方式作調整。例如鈦金屬與4H-SiC之介面以適當溫度下加熱後，可使元件蕭基能障高度從0.65 eV最大增加至1.23 eV (其理想因子也能維持於1左右)。藉由調整能障高度能有效改善Ti- JBS元件反向漏電流過大問題。在本次實驗中最佳元件崩潰電壓操作於1 kV時反向漏電流為10 nA，於順向偏壓為2 V操作下對應電流密度為300~400 A/cm2 。另外為了達成2 Amp之規格，我們設計700 μm x700 μm尺寸相同結構元件，經封裝測試後最佳元件可達1.5 Amp而於反向操作600 V時，漏電流值小於100 μA。

In the thesis, we investigated in the design and fabrication issues of 1200V, 2 Amp junction barrier Schottky diodes. 2-D simulation shows that varying p+ grid spacing between 2-4 μm results in optimal trade-off
between the forward and reverse characteristics.
We have also studied different treatments on Schottky contacts on 4H-SiC for the processing of JBS diodes. For high voltage applications, the control of Schottky barrier is very critical. In our experiments, metal- semiconductor interface properties can be adjusted by RTA process. Take Ti /4H-SiC interface for example, the Schottky barrier height would be increased from 0.65 eV to 1.23 eV with an ideality factor close to 1 by appropriate thermal treatment. As a result, we fabricated 4H-SiC Ti-JBS structures annealed at 450~550℃ for 5 minutes in vacuum. The best device shows a high reverse blocking voltage about 1 kV with a leakage current of 10 nA. Forward current density is about 300~400 A/cm2 at 2 V. Finally, we fabricated 700 um x 700um size JBS devices to increase the conduction current. The best packaged device can deliver 1.5 Amp at 2 V, while the leakage current of device is less than100 μA at -600 V.

[1] A. R. Powell and L. M. Ghezzo, “SiC Material-Progress Status and Potential Roadblocks,” IEEE Proc., vol.90, no.6, pp.942-955, Jun. 2002.
[2] G. R. Fisher and P. Barnes, “Toward a unified view of polytypism in silicon carbide,” Phil. Mag. B, vol.61, no.2, pp.217-236, 1990.
[3] H. Matsunami and T. Kimoto, “Step-controlled epitaxial growth of SiC:High quality homoepitaxy,” Mater. Sci. Eng., vol.20, no.3, pp.125-
166, Aug. 1997.
[4] M. Bhatnagar and B. J. Baliga, “Comparison of 6H-SiC, 3C-SiC, and Si for power devices,” IEEE Trans. Electron Devices, vol.40, no.3,
pp.645-65, Mar. 1993.
[5] K. Shenai, R. S. Scott, and B. J. Baliga, “Optimum semiconductors for high-power electronics,” IEEE Trans. Electron Devices, vol.36, no.9,
pp.1811-1823, Sep. 1989.
[6] B. J. Baliga, Power Semiconductor Devices. Boston, PWS , 1996.
[7] R. Singh, D. C. Capell, A. R. Hefner, J. Lai, and J. W. Palmour, “High-Power 4H-SiC JBS Rectifier,” IEEE Trans. Electron Devices, vol.
49, no.11, Nov. 2002.
[8] B. J. Baliga, Modern Power Devices. New York, Wiley, 1987.
[9] B. J. Baliga, “The pinch rectifier: A low-forward-drop high-speed power diode,” IEEE Electron Device Lett. vol.EDL-5, no.6, pp.194-196,
Jun. 1984.
[10] K. Asano, T. Hayashi, R. Saito, and Y. Sugawara, “High Temperature Static and Dynamic Characteristics of 3.7kV High Voltage 4H-SiC JBS,”
ISPSD’2000. Toulouse, pp.97-100, May. 2000.
[11] F. Dahlquist, J. O. Svedberg, C. M. Zetterling, M. Ӧstling, B. Breitholtz, and H. Lendenmann, “A 2.8kV forward drop JBS diode with low leakage,” Mater. Sci. Forum, vols.338-342, pp.1179-1182, 1999.
[12] B. A. Hull, J. J. Sumakeris, M. J. O’Loughlin, Q. Zhang, J. Richmond, A. R. Powell, ”Performance and Stability of Large-Area 4H-SiC 10kV Junction Barrier Schottky Rectifiers,” IEEE Trans. Electron
Devices, vol.55, no.8, August. 2008.
[13] A. Liu, Y. Tao, Song Bai, Gang Chen, Ling Wang, R. Huang ,Y. Li,
Z. Zhao, “Fabrication and High Temperature Characterization of 1200V 15A 4H-SiC JBS Diode,” Applied Mechanics and Materials, vols.713-
715, pp.1034-1037, 2015.
[14] D. Perrone, M. Naretto, S. Ferrero, L. Scaltrito and C. F. Pirri, “4H- SiC Schottky Barrier Diodes Using Mo-, Ti- and Ni-Based Contacts,”
Mater. Sci. Forum, vols.615-617, pp.647-650, 2009.
[15] A. Kinoshita, T. Nishi, T. Ohyanagi, T. Yatsuo, K. Fukuda, H. Okumura and K. Arai,” Electrical characteristics of Ti/4H-SiC silicidation Schottky barrier diode,” Mater. Sci. Forum, vols. 600-603, pp.643-646,
2007.
[16] A. Kinoshita, T. Ohyanagi, T. Yatsuo, K. Fukuda ,H. Okumura and K. Arai “Fabrication of 1.2kV, 100A, 4H-SiC(0001) and (000-1) junction barrier Schottky diodes with almost same Schottky barrier height,” Mater.
Sci. Forum, vols. 645-648, pp 893-896, 2009.
[17] L. Calcagno, A. Ruggiero, F. Roccaforte, F. L. Via, “Effects of annealing temperature on the degree of inhomogeneity of nickel-silicide/
SiC Schottky barrier,” Journal of Appl. Phys., vol.98, no.2,
pp. 023713-023713-6, July. 2005.
[18] R. Pérez, N. Mestres, J. Montserrat, D. Tournier, and P. Godignon “Barrier inhomogeneities and electrical characteristics of Ni/Ti bi-layer Schottky contacts on 4H–SiC after high temperature treatments,” Phys.
Stat. Solidi (a), vol.202, no.4, pp.692–697, March. 2005.
[19] I. Nikitina, K. Vassilevski, A. Horsfall, N. Wright, A. G O’Neill,
S. K. Ray, K. Zekentes and C. M. Johnson “Phase inhomogeneity and electrical characteristics of nickel silicide Schottky contacts formed on 4H–SiC,” Mater. Sci. Forum, vols.615-617, pp.577-580, 2008.
[20] I. P. Nikitina, K. V. Vassilevski, A. B. Horsfall, N. G. Wright, A. G. O’Neill, C. M. Johnson, T. Yamamoto and R. K. Malhan “Structural
pattern formation in titanium–nickel contacts on silicon carbide following high-temperature annealing,” Semi. Sci. Tech., vol.21, no.7, pp.898-905,
July. 2006.
[21] F. Roccaforte, F. L. Via, V. Raineri, “Highly reproducible ideal SiC Schottky rectifiers: effects of surface preparation and thermal annealing on the Ni/6H-SiC barrier height,” Appl. Phys. A. vol.77, no.6, pp.827-
833, Nov. 2003.

[22] H. S. Lee, “High Power Bipolar Junction Transistors in silicon
Carbide,” ISRN KTH/EKT/FR-2005/6-SE. Dec. 2005.
[23] R. S. Singh, J. A. Cooper, M. R. Melloch, T. P. Chow, and J. W. Palmour, “SiC Power Schottky and PiN Diodes,” IEEE Trans. Electron
Devices. vol.49, no.4, pp. 665-672, Apr. 2002.
[24] R. Singh, S. H. Ryu, J. W. Palmour, A. R. Hefner, J. Lai, “1500V, 4Amp 4H-SiC JBS Diodes,” ISPSD’2000. Toulouse, pp.101-104, May.
2000.
[25] Y. Negoro, K. Katsumoto, T. Kimoto, and Matsunami, “Electronic
behaviors of high-dose phosphorus-ion implanted 4H-SiC(0001),”
Journal of Appl. Phys., vol.96, no.1, July. 2004.
[26] A. Itoh and H. Matsunami “Analysis of Schottky Barrier Heights of Metal/SiC Contacts and Its Possible Application to High-Voltage Rectifying Devices,” Phys. Stat. solidi. (a), vol.162, no.1, pp.389-408, July. 1997.
[27] A. F. Hamida, Z. Ouennoughi, A. Sellai, R. Weiss and H. Ryssel “Barrier inhomogeneities of tungsten Schottky diodes on 4H-SiC,” Semi.
Sci. Tech., vol.23, no.4, pp.045-050, Apr. 2008.
[28] R. Weiss, L. Frey, H. Ryssel “Tungsten, nickel, and molybdenum Schottky diodes with different edge termination,” Applied Surface Sci.
vol.184, no.1, pp.413–418, Dec. 2001.
[29] S. Toumi, A. F. Hamida, L. Boussouar, A. Sellai, Z. Ouennoughi, H. Ryssel “Gaussian distribution of inhomogeneous barrier height in tungsten /4H-SiC (000-1) Schottky diodes,” Microelectronic Engineering,
vol.86, no.3, pp.303–309,Mar. 2009.
[30] A. Kinoshita, T. Nishi, T. Yatsuo and K. Fukuda “Improvement of SBD Electronic Characteristics Using Sacrificial Oxidation Removing the Degraded Layer from SiC Surface after High Temperature Annealing,”
Mater. Sci. Forum, vols.556-557, pp.877-880, 2006.