中国物理B ›› 2004, Vol. 13 ›› Issue (7): 1114-1119.doi: 10.1088/1009-1963/13/7/026
马丽1, 高勇2, 王彩琳2
Ma Li (马丽)a, Gao Yong (高勇)b, Wang Cai-Lin (王彩琳)b
摘要: A novel type of p^+(SiGe)-n^--n^+ heterojunction switching power diode with high-speed capability is presented to overcome the drawbacks of existing power diodes. The improvement is achieved by using a p^+-n^+ mosaic layer as a substitute for the n^+ region in the conventional p^+(SiGe)-n^--n^+ diode to realize an `ideal ohmic' contact for electrons and holes simultaneously. Compared with conventional p^+(SiGe)-n^--n^+ diodes, the ideal ohmic contact p^+(SiGe)-n^--n^+ diodes have about one third of the reverse recovery time and a half of peak reverse recovery current. Furthermore, the softness factor increases nearly two times and the leakage current decreases 1-2 orders of magnitude. These improvements are achieved without resorting special process step to lower the carrier lifetime and thus the devices could be easily integrated into power ICs. The Ge percentage content of p^+(SiGe) layer is an important parameter for the optimal device design.
中图分类号: (Other semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions)