Micro-Raman characterization of the electronic properties of Si-doped GaAs layers grown on patterned substrates

1997 ◽  
Vol 70 (1) ◽  
pp. 69-71 ◽  
Author(s):  
J. Gerster ◽  
J. M. Schneider ◽  
C. Ehret ◽  
W. Limmer ◽  
R. Sauer ◽  
...  
1996 ◽  
Vol 442 ◽  
Author(s):  
F. D. Auret ◽  
G. Myburg ◽  
W. E. Meyer ◽  
P. N. K. Deenapanray ◽  
H. Nordhoff ◽  
...  

AbstractDLTS revealed that each plasma type (He and SiCl4) introduced its own characteristic set of defects. Some of the defects created during He processing and one defect introduced by SiCl4 etching had identical electronic properties to those introduced during high energy (MeV) He ion bombardment. SiC14etching introduced only two prominent defects, one of which is metastable with electronic properties similar to a metastable defect previously reported in high and low energy He-ion bombardment of Si-doped GaAs. IV measurements demonstrated that the characteristics of SBDs fabricated on He-ion processed surfaces were very poor compared to those of control diodes (diodes fabricated on surfaces cleaned by conventional wet etching). In contrast, the properties of SBDs fabricated on SiCl4 etched surfaces were as good as, and in some cases superior to, those of control diodes. SBDs fabricated on annealed (at 450°C for 30 minutes) He-processed samples exhibited improved but still poor rectification. In contrast, SBDs fabricated on annealed SiCl4 etched surfaces had virtually the same characteristics as those fabricated on unannealed SiCl4 etched samples.


2005 ◽  
Vol 87 (24) ◽  
pp. 242105 ◽  
Author(s):  
D. Wang ◽  
C. -C. Tin ◽  
J. R. Williams ◽  
M. Park ◽  
Y. S. Park ◽  
...  

Author(s):  
J. Zimmer ◽  
D. Nielsen ◽  
T.A. Anderson ◽  
M. Schade ◽  
N. Saha ◽  
...  

Abstract The p-n junction of a GaAs light emitting diode is fabricated using liquid phase epitaxy (LPE). The junction is grown on a Si doped (~1018/cm3) GaAs substrate. Intermittent yield loss due to forward voltage snapback was observed. Historically, out of specification forward voltage (Vf) parameters have been correlated to abnormalities in the junction formation. Scanning electron (SEM) and optical microscopy of cleaved and stained samples revealed a continuous layer of material approximately 2.5 to 3.0 urn thick at the n-epi/substrate interface. Characterization of a defective wafer via secondary ion mass spectroscopy (SIMS) revealed an elevated concentration of O throughout the region containing the defect. X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES) data taken from a wafer prior to growth of the epi layers did not reveal any unusual oxidation or contamination. Extensive review of the processing data suggested LPE furnace pressure was the obvious source of variability. Processing wafers through the LPE furnace with a slight positive H2 gas pressure has greatly reduced the occurrence of this defect.


2021 ◽  
Vol 53 (6) ◽  
Author(s):  
Malika Hachemaoui ◽  
Mohamed Meskine ◽  
Allel Mokaddem ◽  
Bendouma Doumi ◽  
Yesim Mogulkoc ◽  
...  

Author(s):  
Maria C. Garcia Toro ◽  
Miguel L. Crespillo ◽  
Jose Olivares ◽  
Joseph T. Graham

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
A. M. Espinoza-Rivas ◽  
M. A. Pérez-Guzmán ◽  
R. Ortega-Amaya ◽  
J. Santoyo-Salazar ◽  
C. D. Gutiérrez-Lazos ◽  
...  

Graphite-coated iron nanoparticles were prepared from magnetite nanoparticles by chemical vapour deposition (CVD) under methane and hydrogen atmosphere. After being purified from carbon excess, graphite-coated iron nanoparticles were tested for morphological and magnetic properties. It was found that, during the thermal process, magnetite nanoparticles 6 nm in size coalesce and transform into graphite-coated iron 200 nm in size, as revealed by scanning electron microscopy (SEM). Raman characterization assessed that high-quality graphite coats the iron core. Magnetic measurements revealed the phase change (magnetite to iron) as an increase in the saturation magnetization from 50 to 165 emu/g after the CVD process.


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