Optimization design and simulation of electric field at interface between substrate and electrode of photoconductive switch
-
摘要: 研究电极结构、SiC与电极连接结构对界面场强的影响，通过电极边缘以及SiC晶体结构的优化降低界面处的电场增强，并通过高压试验测试优化电极结构的击穿电压。结果表明，优化电极倒角以及SiC晶体与电极的界面下埋可有效降低电场增强，在电极为圆倒角及界面使用焊料连接的结构下，使用介质环的器件在电压22 kV时击穿。Abstract: Photoconductive switch can be used in high power microwave system. The breakdown resistance field strength of SiC photoconductive switches is mainly limited by packaging. The packaging method cannot effectively solve the problem of electric field accumulation when the copper electrode leaves the SiC substrate, which leads to the application field strength of SiC far lower than the breakdown resistance strength of SiC crystal. The effects of the structure of the electrode and the connection structure of SiC to the electrode on the interfacial field intensity are studied. The electric field enhancement at the interface is reduced by optimizing the edge of the electrode and the SiC crystal structure. The breakdown voltage of optimized electrode structure is tested. The results show that the electric field enhancement can be effectively reduced by optimizing the electrode chamfering and burying under the interface between SiC crystal and electrode. Under the structure of circular chamfering and interface connecting with solder, the SiC photoconductive switch breaks down at the voltage of 22 kV.
-
Key words:
- photoconductive semiconductor /
- SiC switch /
- electrode /
- interface /
- breakdown field
-
图 5 不同圆柱电极结构场强
Figure 5. Electric field intensity of different cylindrical electrode structures
图 7 界面加焊料后电场强度分布图
Figure 7. Electric field intensity distribution with solder interface
图 8 不同焊料厚度电场最大值
Figure 8. Maximum electric field intensity under different solder thickness
图 9 绝缘介质介电常数30的电场分布
Figure 9. Electric field distribution of dielectric constant 30 of insulating medium
表 1 介质环绝缘材料性能表
Table 1. Insulation material performance
material dielectric strength/(kV·mm−1) dielectric constant thermal conductivity/(W·m−1·K−1) CTE/(K−1) CVD diamond 1000 5.7 1000~2000 1.1×10−6 fused silica 25~40 3.75 1.3 0.55×10−6 undoped SiC 300 10 300~500 4.0×10−6 AlN 17 9 140~180 4.5×10−6 epoxy glue 20~40 3.8~6.2 1.1 (20~60)×10−6 Al2O3 16.9 9.8 35 8.4×10−6 silicone 30~40 2.5~4 1.2 300×10−6 ZrO2 9 29 2.2 10.3×10−6 
下载: 导出CSV
表 2 不同介电常数绝缘介质环材料最大场强
Table 2. Maximum electric field intensity of different dielectric constant insulation rings
material dielectric constant maximum electric field /(kV·mm−1) thickness of the solder is 0.03 mm thickness of the solder is 0.02 mm CVD diamond 5.7 39.7 36.8 Al2O3 9 37.1 32.1 undoped SiC、AlN 10 34.4 27.6 CdWO4 12.8 32.3 28.9 MnWO4 15 30.4 27.3 ZnWO4 17.6 27.7 26.1 CoNb2O6 20 27.2 25.7 Ba5Ta4O15 26 24.0 24.1 ZrO2 30 24.8 22.0 ZrO2 32 24.2 23.5
下载: 导出CSV
-
[1] 张永平. 碳化硅光导开关的制备与性能研究[D]. 上海: 上海师范大学, 2014: 10-40Zhang Yongping. Preparation and properties of SiC photoconductive switch[D]. Shanghai: Shanghai Normal University, 2014: 10-40 [2] Cui H, Yang H, Xu J, et al. Sublinear current-voltage characteristics of linear photoconductive semiconductor switch[J]. IEEE Electr Device L, 2016: 1-1. [3] 宋朝阳. 半绝缘4H-SiC光导开关研究[D]. 西安: 西安电子科技大学, 2015: 20-30Song Chaoyang. Study on semi-insulating 4H-SiC PCSS[D]. Xian: Xidian University, 2015: 20-30 [4] Cao P, Huang W, Guo H, et al. Performance of a vertical 4H-SiC photoconductive switch with AZO transparent conductive window and silver mirror reflector[J]. IEEE T Electron Dev, 2018, 65(5): 2047-2051. doi: 10.1109/TED.2018.2815634 [5] Daniel M, William S, Alan B, et al. High power lateral silicon carbide photoconductive semiconductor switches and investigation of degradation mechanisms[J]. IEEE T Plasma Sci, 2015, 43(6): 2021-2031. doi: 10.1109/TPS.2015.2424154 [6] Sampayan S, Bora M, Brooksby C, et al. High voltage wide bandgap photoconductive switching[J]. Mater Sci Forum, 2015, 821-823: 871-874. doi: 10.4028/www.scientific.net/MSF.821-823.871 [7] Suproniuk M, Kaminski P, Pawlowski M, et al. Current status of modelling the semi-insulating 4H-SiC transient photoconductivity for application to photoconductive switches[J]. Opto-Electron. Rev, 2017, 25(3): 171-180. doi: 10.1016/j.opelre.2017.03.006 [8] 董妍. 高功率光导开关的研究[D]. 成都: 电子科技大学, 2018: 10-30Dong Yan. Research on high power photoconductive semiconductor switch[D]. Chengdu: University of Electronic Science and Technology, 2018: 10-30. [9] Majda E, Suproniuk M, Pawlowski M, et al. Current state of photoconductive semiconductor switch engineering[J]. Opto-Electron Rev, 2018, 26: 92-102. doi: 10.1016/j.opelre.2018.02.003 [10] 许世峰, 何晓雄, 孙飞翔. 光导开关欧姆接触电阻率测量方法研究[J]. 合肥工业大学学报(自然科学版), 2016, 39(7):929-933. (Xu Shifeng, He Xiaoxiong, Sun Feixiang. Research on measurement methods of ohmic contact resistivity of PCSS[J]. Journal of Heifei University of Techonology (Natural Science), 2016, 39(7): 929-933 [11] Hettler C, James C, Dickens J. High electric field packaging of silicon carbide photoconductive switches[C]//Proc of PPC. 2009. [12] Fessler C, Kelkar K, Nunnally W, et al. Investigation of high electric fields at the electrode-SiC interface in photo-switches[C]//Proc of PPC. 2008. [13] 曹鹏辉. 采用透明电极的垂直型4H-SiC光导开关的研究[D]. 西安: 西安电子科技大学, 2017: 20-40Cao Penghui. Research on vertical 4H-SiC PCSS with transparent electrode[D]. Xian: Xidian University, 2017: 20-40 [14] Sullivan J. High power operation of a nitrogen doped, vanadium compensated, 6H-SiC extrinsic photoconductive switch[J]. Appl Phys Lett, 2014, 104(17): 172106. doi: 10.1063/1.4875258 [15] 章林文, 夏连胜, 谌怡, 等. 介质壁加速器关键技术[J]. 高电压技术, 2015, 41(6):1769-1775. (Zhang Linwen, Xis Liansheng, Shen Yi, et al. Technologies of dielectric wall accelerator[J]. High Voltage Engineering, 2015, 41(6): 1769-1775 [16] James C, Hettler C, Dickens J. High-purity semi-insulating 4H-SiC as a high-voltage switch material[C]//Proc of IPMC. 2010. [17] 董妍. 高功率光导开关的研究[D]. 成都: 电子科技大学, 2018: 1-11Dong Yan. Research on high power photoconductive semiconductor switch[D]. Chengdu: University of Electronic Science and Technology of China, 2018: 1-11 [18] 刘金进. 碳化硅光导开关耐压结构设计与仿真研究[D]. 上海: 上海师范大学, 2021: 6-12Liu Jinjin. Design and simulation of silicon carbide photoconductive semiconductor switches withstanding high voltage[D]. Shanghai: Shanghai Normal University, 2021: 6-12 -
点击查看大图
计量
- 文章访问数: 728
- HTML全文浏览量: 396
- PDF下载量: 69
- 被引次数: 0
