A novel high-voltage light punch-through carrier stored trench bipolar transistor with buried p-layer

• Published in: Chinese physics B Vol. 21; no. 6; pp. 573 - 578
• Main Author: 王颖 兰昊 曹菲 刘云涛 邵雷 张金平 李泽宏 张波 李肇基
• Format: Journal Article
• Language: English
• Published: 01.06.2012
• Subjects: Bipolar transistors; Carriers; Doping; Drift; Electric fields; Electric potential; Electrical junctions; Semiconductor devices; Trenches; 双极晶体管; 存储; 掺杂浓度; 沟槽; 电场分布; 穿通; 载流子; 高电压
• ISSN: 1674-1056; 2058-3834; 1741-4199
• DOI: 10.1088/1674-1056/21/6/068504

A novel high-voltage light punch-through（LPT） carrier stored trench bipolar transistor（CSTBT） with buried p-layer（BP） is proposed in this paper.Since the negative charges in the BP layer modulate the bulk electric field distribution,the electric field peaks both at the junction of the p base/n-type carrier stored（N-CS） layer and the corners of the trench gates are reduced,and new electric field peaks appear at the junction of the BP layer/N drift region.As a result,the overall electric field in the N drift region is enhanced and the proposed structure improves the breakdown voltage（BV） significantly compared with the LPT CSTBT.Furthermore,the proposed structure breaks the limitation of the doping concentration of the N-CS layer（NN CS） to the BV,and hence a higher NN CS can be used for the proposed LPT BP-CSTBT structure and a lower on-state voltage drop（Vce（sat）） can be obtained with almost constant BV.The results show that with a BP layer doping concentration of NBP = 7 × 10^15 cm^-3,a thickness of LBP = 2.5 μm,and a width of WBP = 5 μm,the BV of the proposed LPT BP-CSTBT increases from 1859 V to 1862 V,with NN CS increasing from 5 × 10^15 cm^-3 to 2.5 × 10^16 cm^-3.However,with the same N-drift region thickness of 150 μm and NN CS,the BV of the CSTBT decreases from 1598 V to 247 V.Meanwhile,the Vce（sat） of the proposed LPT BP-CSTBT structure decreases from 1.78 V to 1.45 V with NN CS increasing from 5 × 10^15 cm^-3 to 2.5 × 10^16 cm^-3.