Research On High-performance SiGe HBT Structure Design And Manufacturing

With rapid development in modern mobile communication and microwavecommunication, low-cost, high performance RF/microwave devices are stronglydemanded in communication market. Currently, almost every IC manufacturers in theworld have joined in the ranks of the development of SiGe HBT. With the developmentof SiGe technology, the SiGe technology will be used in analog and digital region.This paper based on the physical properties of strained SiGe materials, establishedthe main electrical parameter model including current gain, cut-off frequency, maximumoscillation frequency and so on. The generation mechanism of SiGe HBT heterojunctionbarrier effects and parasitic energy barrier is analyzed. The impact of heterojunctionbarrier effects and parasitic energy barrier on device electrical properties is also studied.The measurement including added SiGe intrinsic layer, introducing Ge in the collectornear the base side to form the homogeneous collector junction is produced to suppressheterojunction barrier effects and parasitic energy barrier. On the basis of the above, thesimulations were done using ISE software. Our simulation studies include the impact ofphysical parameters and device geometry parameters on the electrical properties of SiGeHBT, especially analyzing the frequency characteristics. Then we obtain the optimizedSiGe HBT device structure. The cut-off frequency is up to 95GHz, the maximumoscillation frequency is up to 170GHz and the maximum current gain is 134. Based onthe given device structure, the process of dual-poly HBT using non-selective epitaxywere achieved.