Abstract
This paper presents a comparative study of GaAs carbon doping by molecular beam epitaxy (MBE) and chemical beam epitaxy (CBE), using a heated graphite filament and trimethylgallium (TMG), respectively, as sources of carbon. With a growth rate twice higher, CBE allowed us to obtain higher hole concentrations (3 × 10 20 cm -3) than MBE (8 × 10 19 cm -3). The most striking feature was the difference in minority carrier lifetimes, which were up to two orders of magnitude lower in MBE samples. Heterojunction bipolar transistor structures were grown by the two techniques, using a carbon-doped base. Poor performances were obtained on MBE structures. But devices grown by CBE, with a base doping level of 5 × 10 19 cm -3 and a base thickness of 50 nm, exhibited DC current gain as high as 194, with an excellent uniformity of the base sheet resistance.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
