00000cab a22000003a 4500 UP-99796217609500782 Buklod 20231007234452.0 m |o d | ta 101014s xx d | ||r ||||| || DENGII eng Singh, D.V. Effect of band alignment and density of states on the collector current in p-Si/n-Si1-yCy p-Si HBTs. pp. 425-432 p-Si/n-Si1-yCy/p-Si heterojunction bipolar transistors with varying carbon fractions in the base were grown by rapid thermal chemical vapor deposition (RTCVD), to better understand the potential of Si1-yCy in enhancing the performance of Si-based bipolar technology. The band line-up issues which make Si1-yCy a desirable choice for forming the base region in a p-n-p HBT are discussed. Electrical measurements performed on the p-Si/n-Si1-yCy/p-Si HBTs (y=0.6, 0.8 at.%) are used to extract important information regarding the electronic properties of the Si/Si1-yCy material system, e.g., the bandgap reduction in Si1-yCy compared to Si and minority carrier recombination lifetime in Si1-yCy. Temperature dependent measurements of the collector current were performed to extract the bandgap narrowing at the Si/Si1-yCy heterojunction. This paper includes a detailed analysis of the impact of heavy doping and reduced density of states in Si1-yCy compared to Si on the extraction of the energy bandgap offset, and on the collector current of p-n-p HBTs. The impact of the reduced density of states on the design of p-n-p Si/Si1-yCy HBTs is discussed. The measured value of the energy band offset is (65 meV/at.% C) very close to previously measured values of the conduction band offset at the Si/Si1-yCy heterojunction. The results are thus consistent with a band line-up at the Si/Si1-yCy interface that is dominated by a conduction band offset with little if any valence band offset. RTCVD. Si-SiC-Si. Si-based bipolar technology. Bandgap narrowing. Bandgap reduction. Chemical vapor deposition. Collector current. Density of states reduction. Electronic properties. Energy bandgap offset. Heavy doping. Minority carrier recombination lifetime. P-n-p HBT. Rapid thermal CVD. Temperature dependent measurements. Si/Si1-yCy material system. p-Si/n-Si1-yCy/p-Si HBTs. IEEE Transactions on electron devices 50, 2 (2003). FO UPD DENG-II Article