Characteristics of Si3N4/Si/ n -GaAs metal-insulator-semiconductor interfaces grown on GaAs(111)B substrate

• Published in: Applied physics letters Vol. 69; no. 20; pp. 3025 - 3027
• Main Authors: Park, Dae-Gyu, Diatezua, Deda M., Chen, Zhi, Mohammad, S. Noor, Morkoç, Hadis
• Format: Journal Article
• Language: English
• Published: 11-11-1996
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.116827

Interfacial properties of Al/Si3N4/Si/n-GaAs metal-insulator-semiconductor (MIS) capacitors grown on GaAs(111)B prepared with a combination of in situ molecular beam epitaxy and chemical vapor deposition techniques are presented. The density of the surface states in the high 1010 eV−1 cm−2 near the GaAs midgap for the GaAs grown at 575 and 625 °C was obtained. The MIS structure with GaAs homoepitaxial layer grown at 625 °C, showing smoother surface morphology than the surface grown at 575 °C, exhibited small hysteresis which was as small as 30 mV under a field excursion of 1.5 MV/cm. The presence of a 1 MHz frequency response at 77 K requires that the traps be within 60 meV of the conduction band edge of GaAs and confirms the unpinned GaAs surface Fermi energy within GaAs band gap.