SiGe HBTs featuring f_T ≫400GHz at room temperature

Abstract

This paper presents the results of investigations on process thermal budget reduction in order to increase the operation frequency of SiGe HBTs. We describe the variations of dc and ac characteristics of the devices with the spike annealing temperature. Record peak f T values of 410GHz and 640GHz are reported at room and cryogenic temperatures respectively.

Advanced process modules and architectures for half-terahertz SiGe:C HBTs

“…Using P for the emitter requires a lower RTA temperature. This is beneficial for realizing narrow base widths, but reduces the activation of dopants in the external base [16].…”

“…While perspectives still exist to further increase f max , there are uncertainties as to whether very large f max (>>500GHz), requiring high f T , can be achieved as f T and f max scaling seem to require conflicting optimizations. An example was given in [16], where a record f T of 410 GHz was associated with low f max . In this work lower thermal budgets have been shown to push the f T to higher values at the expense of lower base doping activation, and hence higher R b (lower f max ).…”

Investigation of SiGe HBT potentialities under cryogenic temperature

“…As discussed previously, a huge base resistance (5 times higher than 'standard' technology [7]) limits the noise performances. Thus, the standard technology ifr / f MAx = 260 GHz / 315 GHz) is investigated to determine its noise performances and validate the noise model.…”

A 200 GHz Heterodyne Image Receiver With an Integrated VCO in a SiGe BiCMOS Technology

“…Traditionally, III-V compound technologies have been favored for such high frequency bands, but the recent advancement of Si devices has enabled Si-based technologies for applications in this exciting frontier [1], [2]. There have been growing efforts to develop Si-based image receivers in this frequency band, but most of them were based on the direct detection approach [3].…”