Open AccessRecent progress in GaInAsSb thermophotovoltaics grown by organometallic vapor phase epitaxy
Author(s) -
C A Wang,
H K Choi,
D.C. Oakley,
G.W. Charache
Publication year - 1998
Language(s) - English
Resource type - Reports
DOI - 10.2172/307841
Subject(s) - trimethylindium , thermophotovoltaic , epitaxy , photoluminescence , misorientation , materials science , substrate (aquarium) , dimethylzinc , analytical chemistry (journal) , dopant , crystallography , metalorganic vapour phase epitaxy , chemistry , optoelectronics , doping , nanotechnology , metallurgy , microstructure , common emitter , oceanography , layer (electronics) , chromatography , zinc , geology , grain boundary
Studies on the materials development of Ga{sub 1{minus}x}In{sub x}As{sub y}Sb{sub 1{minus}y} alloys for thermophotovoltaic (TPV) devices are reviewed. Ga{sub 1{minus}x}In{sub x}As{sub y}Sb{sub 1{minus}y} epilayers were grown lattice matched to GaSb substrates by organometallic vapor phase epitaxy (OMVPE) using all organometallic precursors including triethylgallium, trimethylindium, tertiarybutylarsine, and trimethylantimony with diethyltellurium and dimethylzinc as the n- and p-type dopants, respectively. The overall material quality of these alloys depends on growth temperature, In content, V/III ratio, substrate misorientation, and to a lesser extent, growth rate. A mirror-like surface morphology and room temperature photoluminescence (PL) are obtained for GaInAsSb layers with peak emission in the wavelength range between 2 and 2.5 {micro}m. The crystal quality improves for growth temperature decreasing from 575 to 525 C, and with decreasing In content, as based on epilayer surface morphology and low temperature PL spectra. A trend of smaller full width at half-maximum for low temperature PL spectra is observed as the growth rate is increased from 1.5 to 2.5 and 5 {micro}m/h. In general, GaInAsSb layers grown on (100) GaSb substrates with a 6{degree} toward (111)B misorientation exhibited overall better material quality than layers grown on the more standard substrate (100)2{degree} toward (110). Consistent growth of high performance lattice-matched GaInAsSb TPV devices is also demonstrated