Steady State Temperature Study on RF LDMOS with Structure Modification

Xiaohong Sun, Haodong Wu, Qiang Chen, Huai Gao

Department of Electronic System, the Royal Institute of Technology-KTH, Stockholm, Sweden.
Key Laboratory of Modern Acoustics, Institute of Acoustics, Nanjing University,Nanjing, China.
National ASIC System Engineering Center, Southeast University, Nanjing, China.

DOI: 10.4236/eng.2012.47049                

Abstract

This paper is devoted to temperature analysis on power RF LDMOS with different feature parameters of die thickness, pitch S length and finger width. The significance of these three parameters is determined from temperature comparison obtained by 3D Silvaco-Atlas device simulator. The first three simulations focus on temperature variation with the three factors at different output power density respectively. The results indicate that both the thinner die thickness and the broaden pitch S length have distinct advantages over the shorter finger width. The device, at the same time, exhibits higher temperature at a larger output power density. Simulations are further carried out on structure with combination of different pitch s length and die thickness at a large 1W/mm output power density and the temperature reduction reaches as high as 55%.

Keywords

RF LDMOS; 3D Steady-State Temperature; Die Thickness; Pitch S length; Finger Width;

Conflicts of Interest

The authors declare no conflicts of interest.

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