MBE growth and optical characterization of InGaN/AlGaN multi-quantum wells
- Boston Univ., MA (United States)
The authors report the growth of InGaN/AlGaN MQWs on c-plane sapphire by electron cyclotron resonance assisted molecular beam epitaxy (ECR-MBE). Two types of structures were investigated; one employing a GaN and the other a ALGaN barrier layer. The first structure consists of five periods of 80 {angstrom} thick In{sub 0.09}Ga{sub 0.91}N wells separated by 90 {angstrom} thick GaN barriers. The second structure consists of seven periods of 120 {angstrom} thick In{sub 0.35}Ga{sub 0.65}N wells and Al{sub 0.1}Ga{sub 0.9}N barriers. The substrate temperature was kept constant during the growth of both the wells and the barriers, thus avoiding the need for any temperature cycling during the growth, which may lead to interfacial contamination. The films were characterized by cross sectional transmission electron microscopy (TEM), room temperature photoluminescence (PL) and sub-micron resolution luminescence microscopy. TEM images show sharp and abrupt interfaces, thus confirming the high interfacial quality of the MQW structures. Both structures exhibit strong RT luminescence emission peaking at 387 nm (FWHM = 16 nm) for the In{sub 0.09}Ga{sub 0.91}N/GaN structure and at 463 nm (FWHM = 28 nm) for the In{sub 0.35}Ga{sub 0.65}N/Al{sub 0.1}Ga{sub 0.9}N structure. The high resolution luminescence microscopy studies reveal that the radiative recombination for the InGaN quantum wells is 60--7- times more efficient than for the underlying GaN film.
- Sponsoring Organization:
- Advanced Research Projects Agency, Washington, DC (United States)
- OSTI ID:
- 580992
- Report Number(s):
- CONF-961202--; ISBN 1-55899-353-3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Optical properties of AlGaN quantum well structures
Surface potential measurements on GaN and AlGaN/GaN heterostructures by scanning Kelvin probe microscopy