Title :
High-gain InGaP/GaAs HBTs with compositionally graded InxGa1-xAs bases grown by molecular beam epitaxy
Author :
Joe, Jin Hyoun ; Missous, Mohamed
Author_Institution :
Dept. of Electr. Eng. & Electron., Univ. of Manchester Inst. of Sci. & Technol., UK
Abstract :
InGaP/GaAs single heterojunction bipolar transistors (SHBTs) with compositionally graded base have been successfully grown by solid source MBE using a GaP decomposition source. They were processed into 60×60 μm2 emitter contacts. The device characteristics of HBTs with InxGa1-xAs graded bases (0→0.05, 0→0.1) are compared with non-graded base HBTs to investigate the optimum-grading profile. The average current gains of the non-graded base, the 5% graded base and the 10% graded base are 174, 321 and 342, respectively. To our knowledge, these current gains are the highest value ever reported in InGaP/GaAs HBTs with a compositionally graded base and with base sheet resistances of ∼200 ohms/square. These high current gains at the high base doping used attest to the very high quality of the graded base HBT materials.
Keywords :
III-V semiconductors; doping profiles; gallium compounds; heterojunction bipolar transistors; indium compounds; molecular beam epitaxial growth; optimisation; semiconductor device measurement; 60 micron; GaP decomposition sources; HBT average current gain; InGaP-InGaAs-GaAs; SHBT compositionally graded InGaAs bases; base sheet resistance; emitter contact size; grading profile optimization; high base doping levels; high-gain InGaP/GaAs HBT; molecular beam epitaxy; nongraded base HBT; single heterojunction bipolar transistors; solid source MBE; Contacts; Doping; Electron devices; Gallium arsenide; Gold; Heterojunction bipolar transistors; Molecular beam epitaxial growth; Sheet materials; Solids; Temperature;
Conference_Titel :
Electron Devices for Microwave and Optoelectronic Applications, 2002. EDMO 2002. The 10th IEEE International Symposium on
Print_ISBN :
0-7803-7530-0
DOI :
10.1109/EDMO.2002.1174964
