4H-SiC power BJTs with high current gain and low on-resistance
2007 (English)In: Materials Science Forum, ISSN 0255-5476, Vol. 556-557, 767-770 p.Article in journal (Refereed) Published
4H-SiC BJTs have been fabricated with varying geometrical designs. The maximum value of the current gain was about 30 at I-c=85 mA, V-CE=14 V and room temperature (RT) for a 20 mu m emitter width structure. A collector-emitter voltage drop V-CE of 2 V at a forward collector current 55 mA (J(C) = 128 A/cm(2)) was obtained and a specific on-resistance of 15.4 m Omega center dot cm(2) was extracted at RT. Optimum emitter finger widths and base-contact implant distances were derived from measurement. The temperature dependent DC IN characteristics of the BJTs have been studied resulting in 45 % reduction of the gain and 75 % increase of the on-resistance at 225 degrees C compared to RT. Forward-bias stress on SiC BJTs was investigated and about 20 % reduction of the initial current gain was found after 27.5 hours. Resistive switching measurements with packaged SiC BJTs were performed showing a resistive fast turn-on with a VCE fall-time of 90 ns. The results indicate that significantly faster switching can be obtained by actively controlling the base current.
Place, publisher, year, edition, pages
2007. Vol. 556-557, 767-770 p.
bipolar junction transistors; current gain; switching; degradation
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-7933DOI: 10.4028/www.scientific.net/MSF.556-557.767ISI: 000249653900182ScopusID: 2-s2.0-38449112149OAI: oai:DiVA.org:kth-7933DiVA: diva2:13116
QC 201008192008-01-302008-01-302010-08-19Bibliographically approved