Study of emitter width effects on β_F,f_Tandf_maxof 200 GHz SiGe HBTs by DD, HD and EB device simulation

Abstract

This paper studies the effect of emitter width on the dc current gain, β F , and ac figures of merit, cut-off frequency, f T , and maximum oscillation frequency, f max , of realistic structures for 200 GHz SiGe heterojunction bipolar transistors (HBTs) using two-dimensional drift-diffusion (DD), hydrodynamic (HD) and energy balance (EB) simulations. The carrier transport models used are briefly presented. The SiGe-HBTs studied have a base thickness of 15 nm. Results of the three transport models are shown and analyzed, for the different emitter geometries.

Hydrodynamic device simulation of 200 GHz SiGe heterojunction bipolar transistors

“…SiGe-HBT 2D geometry, characteristics and details of the model were shown in [3,15]. The SiGe-HBT has a base thickness of 15 nm, see Fig.…”

“…In two previous papers [3,4], we used ATLAS simulation tool [5] to do a comparative study of emitter width effect on β F , f T and f max and to verify a new analytical model for high-frequency noise of realistic 200 GHz SiGe-HBTs [6].…”

“…In a previous paper [3], results of realistic 200 GHz SiGeHBTs was performed using HD two dimensional simulations. The results presented were for collector-base voltages below the breakdown voltage assuming that energy and high field mobility relaxation times are equals.…”

Analytical modelling of 200 GHz SiGe HBT high-frequency noise parameters

“…simulations that use the field impedance method from the ATLAS device simulator [19]. The simulated device has an emitter area of A E0 = 0.15 × 26 μm 2 [20,21]. The experimental results are for a 200 GHz SiGe HBT with CBEBC contact configuration with an emitter area of A E0 = 0.15 × 10 μm 2 .…”

Numerical simulations of rear point-contacted solar cells on 2.2 Ωcm p-type c-Si substrates

“…In this paper, we use our experience on bipolar device modeling for developing a 3D numerical model using commercial TCAD software (Silvaco‐ATLAS, Silvaco Inc., Santa Clara, CA, USA ) to be applied to passivated emitter and rear cell‐type solar cells fabricated on 2.2 Ωcm float zone p‐type substrates. The main feature of these cells is the application of the laser processing of Al 2 O 3 /SiC x stacks to define the point‐like rear contact.…”