Thermal stability improvement of a multiple finger power SiGe heterojunction bipolar transistor under different power dissipations using non-uniform finger spacing

• Published in: Chinese physics B Vol. 20; no. 1; pp. 667 - 671
• Main Author: 陈亮 张万荣 金冬月 沈佩 谢红云 丁春宝 肖盈 孙博韬 王任卿
• Format: Journal Article
• Language: English
• Published: IOP Publishing 2011
• Subjects: SiGe异质结双极晶体管; 功率器件; 异质结双极型晶体管; 非均匀性; 高热稳定性
• ISSN: 1674-1056; 2058-3834
• DOI: 10.1088/1674-1056/20/1/018501

A method of non-uniform finger spacing is proposed to enhance thermal stability of a multiple finger power SiGe heterojunction bipolar transistor under different power dissipations. Temperature distribution on the emitter fingers of a multi-finger SiGe heterojunction bipolar transistor is studied using a numerical electro-thermal model. The results show that the SiGe heterojunction bipolar transistor with non-uniform finger spacing has a small temperature difference between fingers compared with a traditional uniform finger spacing heterojunction bipolar transistor at the same power dissipation. What is most important is that the ability to improve temperature non-uniformity is not weakened as power dissipation increases. So the method of non-uniform finger spacing is very effective in enhancing the thermal stability and the power handing capability of power device. Experimental results verify our conclusions.