Properties of metamorphic materials and device structures on GaAs substrates

• Published in: Journal of crystal growth Vol. 251; no. 1; pp. 804 - 810
• Main Authors: Hoke, W.E., Kennedy, T.D., Torabi, A., Whelan, C.S., Marsh, P.F., Leoni, R.E., Lardizabal, S.M., Zhang, Y., Jang, J.H., Adesida, I., Xu, C., Hsieh, K.C.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.04.2003; Elsevier
• Subjects: A1. Line defects; A3. Molecular beam epitaxy; Applied sciences; B2. Semiconducting ternary materials; B3. High electron mobility transistors; Electronics; Exact sciences and technology; Microelectronic fabrication (materials and surfaces technology); Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Transistors; B2. Semiconducting ternary materials; 81.15.Hi; A3. Molecular beam epitaxy; B3. High electron mobility transistors; 81.05.Ea; A1. Line defects; Buffer layer; Performance evaluation; Metamorphic transistor; Low noise amplifier; Photoluminescence; Roughness; Dislocation density; High electron mobility transistor; Microelectronic fabrication; p i n photodiodes; Molecular beam epitaxy; Microstructure; 81,15,Hi: 81.05.Ea Al. Line defects
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/S0022-0248(02)02374-6

Metamorphic layer structures grown on GaAs substrates have been characterized and fabricated into high quality electrical and optical devices. The root mean square surface roughness of the metamorphic films is <15 Å, which is smaller than most device layer thicknesses. Cross-sectional transmission electron micrographs show that the dislocations necessarily formed during growth of the metamorphic buffer layer are predominantly contained in the buffer layer. Subsequently grown device layers exhibit planar interfaces. From plan view micrographs, the dislocation density is approximately 10 6 cm −2 or less. The mobility of metamorphic high electron mobility transistor (HEMT) structures increases with indium content and is essentially equivalent to the mobility of the same structures grown lattice matched on InP substrates. The room temperature photoluminescence of transistor quantum wells is not degraded by growth on metamorphic buffer layers. High gain, low noise amplifiers have been demonstrated with long-term reliability. Metamorphic PIN photodiodes exhibit the same responsivities and bandwidths as InP PIN photodiodes. An integrated metamorphic PIN–HEMT layer structure has been grown. The responsivity of the PIN was 0.52 A/W with an unoptimized bandwidth approaching 30 GHz. The metamorphic high electron mobility transistor exhibited typical performance for current, transconductance, and pinch-off.