MBE Growth and Properties of GaN, InGaN and GaN/InGaN Quantum Well Structures for Laser Diode Applications
Final rept. 15 Sep 1995-15 Oct 1999
NORTH CAROLINA STATE UNIV AT RALEIGH
Pagination or Media Count:
The program topic was changed to growth of III-V nitrides by MBE by mutual agreement with J. Zavada of ARO. Growth of III-V nitrides by molecular beam epitaxy NIBE has been studied using rf nitrogen plasma sources. Plasma sources from three different vendors have been tested. All three of the sources have been used to grow high quality GaN. However, the EPI rf source produces an optical emission spectrum that is very rich in the active nitrogen species of 1st-Positive excited nitrogen molecules and nitrogen atoms. GaN growth rates at 800 deg C of 1 micrometerhr have been achieved using this source. The MBE-grown GaN films are deposited homoepitaxially on high quality MOVPE-grown GaNSiC substrates. With the growth conditions for high quality undoped GaN as a baseline, a detailed study of Mg doping for p-type GaN was performed. An acceptor incorporation of 2x1019 cm-3 was measured by both CV and SIMS for a doping source temperature of 290 deg C. However, a faceted 3-dimensional growth mode was observed by RHEED during Mg doping of GaN. Additional studies suggest an interdependence between Mg incorporation and growth surface morphology. Quantum well structures made from the inGaN ternary alloy were grown using a modulated beam MBE method. With this technique, quantum well compositions were controllable grown with visible luminescence ranging from 4OOnm to 515nm depending on indium mole fraction. Light emitting diode test structures, combin in g Mg p-type doping with InGaN quantum wells, were fabricated and tested.
- Inorganic Chemistry
- Lasers and Masers
- Quantum Theory and Relativity