Compared with BVcEo, BVcEs is more related to collector optimization and more practical significance, so that BVcEs × fT rather than BVcEo ×fT is employed in representing the limit of the product of the brea...Compared with BVcEo, BVcEs is more related to collector optimization and more practical significance, so that BVcEs × fT rather than BVcEo ×fT is employed in representing the limit of the product of the breakdown voltage-cutoff frequency in SiGe HBT for collector engineering design. Instead of a single decrease in collector doping to improve BVcEs × fT and BVcEo × fT, a novel thin composite of N- and P＋ doping layers inside the CB SCR is presented to improve the well-known tradeoff between the breakdown voltage and cut-off frequency in SiGe HBT, and BVCES and BVCEO are improved respectively with slight degradation in fTAs a result, the BVcEs × fT product is improved from 537.57 to 556.4 GHz.V, and the BVcEo ×fT product is improved from 309.51 to 326.35 GHz.V.展开更多
基金supported by the National Natural Science Foundation of China(Nos.60776051,61006059,61006044)the Beijing Natural Science Foundation(Nos.4082007,4143059,4142007,4122014)the Beijing Municipal Education Committee(Nos.KM200710005015,KM200910005001)
文摘Compared with BVcEo, BVcEs is more related to collector optimization and more practical significance, so that BVcEs × fT rather than BVcEo ×fT is employed in representing the limit of the product of the breakdown voltage-cutoff frequency in SiGe HBT for collector engineering design. Instead of a single decrease in collector doping to improve BVcEs × fT and BVcEo × fT, a novel thin composite of N- and P＋ doping layers inside the CB SCR is presented to improve the well-known tradeoff between the breakdown voltage and cut-off frequency in SiGe HBT, and BVCES and BVCEO are improved respectively with slight degradation in fTAs a result, the BVcEs × fT product is improved from 537.57 to 556.4 GHz.V, and the BVcEo ×fT product is improved from 309.51 to 326.35 GHz.V.
