Metalorganic chemical vapor deposition-regrown Ga-rich InGaP films on SiGe virtual substrates for Si-based III-V optoelectronic device applications
Kohen, David A.
Hwang, Jeong Woo
Shin, Jae Cheol
Date of Issue2017
School of Electrical and Electronic Engineering
Singapore-MIT Alliance Programme
Ga-rich InGaP materials are attractive applications for yellow-green spectral range optoelectronics such as light-emitting diodes and solar cells on silicon substrate. Bulk, Ga-rich InGaP films grown by metalorganic chemical vapor deposition on SiGe virtual substrates were investigated in the V/III compositional ratio range of 44.3–402 using chamber pressures from 100 to 200 mbar. These films were nominally lattice matched to the SiGe virtual substrate with a bandgap energy of 2.07–2.09 eV at low temperature (10 K). The authors show that the surface morphology of the Ga-rich InGaP films was dependent on the growth conditions, including the V/III gas phase ratio, pressure, and growth rate. By optimizing the growth conditions, the authors achieved improved surface morphologies of the Ga-rich InGaP films. The hillock density of the films produced using a V/III gas phase ratio of 44.3 and 75.4, a growth pressure of 100 mbar, and a growth rate of 0.9 μm/h was about an order of magnitude lower (30.3–50 × 104 cm−2) than that observed using higher V/III gas phase ratios such as 201 and 402. An increase in luminescence efficiency of Ga-rich InGaP materials was observed when the hillock density is lower. The authors discuss the mechanisms of the hillock formation.
Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films
© 2017 American Vacuum Society. This paper was published in Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films and is made available as an electronic reprint (preprint) with permission of American Vacuum Society. The published version is available at: [http://dx.doi.org/10.1116/1.4979272]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.