Comprehensive study of an InGaP/AlGaAs/GaAs heterojunction bipolar transistor with a continuous conduction-band structure

Abstract

A newly designed In 0.49 Ga 0.51 P/Al x Ga 1−x As/GaAs heterojunction bipolar transistor with a continuous conduction-band structure is theoretically analysed and investigated. By introducing a compositionally linear-graded AlGaAs layer into conventional InGaP/GaAs heterojunctions, a zero conduction-band discontinuity and a completely deleted potential spike can be obtained. Due to the suppression of potential spikes at the emitter/base junction, the studied device shows better dc performances such as a lower offset voltage ( 25 mV), lower saturation voltage ( 0.3 V), uniform current gain (∼40) and lower turn-on voltage (∼1.15 V). In addition, better ac performances are achieved. Consequently, the designed structure provides promise for high-performance analogue, digital and microwave device applications.

A New InP/InGaAs Double Heterojunction Bipolar Transistor With a Step-Graded InAlGaAs Collector Structure

“…1. In this letter, a designed step-graded junction structure is employed, and the theoretical analysis and simulation are made by using the 2-D simulator ATLAS [15]. The distribution of the B-C barrier in the depleted collector region makes it possible for electrons with sufficient kinetic energy to transport over the conduction band spikes even at zero bias.…”

Comprehensive investigation on emitter ledge length of InGaP∕GaAs heterojunction bipolar transistors

“…[14][15][16] The material parameters used in this simulation are listed in Table II. These values are selected to be consistent with previous reports.…”

“…The theoretical analysis and simulation are made by using a twodimensional semiconductor simulator ATLAS. [14][15][16] The dependencies of important physical properties ͑such as recombination rates, electron densities, energy band diagrams͒ on the emitter ledge length are studied and demonstrated. In addition, experimental devices are fabricated and compared in this work.…”

AlGaAs/InGaP interfaces in structures prepared by MOVPE

“…In the past, GaAs/Al x Ga 1Àx As/InGaP structures were used for the preparation of HBTs with improved electrical parameters [8,9]. The band offset of the Al x Ga 1Àx As/In 0.5 Ga 0.5 P system was studied only with samples prepared by liquid phase epitaxy (LPE) [10,11].…”