2026-09-20T13:13:03Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/20011 2023-07-10 col_2142_5131 col_2142_8888 com_2142_5130 com_2142_8887 com_2142_234

Stillman, Gregory E. Cunningham, Brian Thomas 2011-05-07T12:25:57Z 2011-05-07T12:25:57Z 10000-01-01 1990 A dilute mixture of CCl$\sb4$ in high purity H$\sb2$ has been used as a carbon dopant source for $\rm Al\sb{x}Ga\sb{1-x}As$ grown by low pressure metalorganic chemical vapor deposition (MOCVD). To understand the mechanism for carbon incorporation from CCl$\sb4$ doping and to provide experimental parameters for the growth of carbon doped device structures, the effects of various crystal growth parameters on CCl$\sb4$ doping have been studied, including growth temperature, growth rate, V/III ratio, Al composition, and CCl$\sb4$ flow rate. Although CCl$\sb4$ is an effective p-type dopant for MOCVD $\rm Al\sb{x}Ga\sb{1-x}As$, injection of CCl$\sb4$ into the reactor during growth of InP resulted in no change in the carrier concentration or carbon concentration. Abrupt, heavy carbon doping spikes in GaAs have been obtained using CCl$\sb4$ without a dopant memory effect. By annealing samples with carbon doping spikes grown within undoped, n-type, and p-type GaAs, the carbon diffusion coefficient in GaAs at 825$\sp\circ$C has been estimated and has been found to depend strongly on the GaAs background doping. Heavily carbon doped $\rm Al\sb{x}Ga\sb{1-x}As$/GaAs superlattices have been found to be more stable against impurity induced layer disordering (IILD) than Mg or Zn doped superlattices, indicating that the low carbon diffusion coefficient limits the IILD process. Carbon doping has been used in the base region on an Npn AlGaAs/GaAs heterojunction bipolar transistor (HBT). Transistors with 3 x 10 $\mu$m self-aligned emitter fingers have been fabricated which exhibit a current gain cutoff frequency of f$\sb{\rm t}$ = 26 GHz. Made available in DSpace on 2011-05-07T12:25:57Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9026165.pdf: 2498020 bytes, checksum: 2cbfb62f56d8f06ac673ff0fdcb7630a (MD5) Previous issue date: 1990 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:40:57Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:17:39-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9026165 (UMI)AAI9026165 http://hdl.handle.net/2142/20011 eng Copyright 1990 Cunningham, Brian Thomas Chemistry, Organic Engineering, Electronics and Electrical Physics, Condensed Matter Carbon doping of compound semiconductor epitaxial layers grown by metalorganic chemical vapor deposition using carbon tetrachloride text Electrical and Computer Engineering Electrical and Computer Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.