Humidity-dependent stability of amorphous germanium nitrides fabricated by plasma nitridation

Journal Article · Mon Oct 15 00:00:00 EDT 2007 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.2799260· OSTI ID:21013722

Kutsuki, Katsuhiro; Okamoto, Gaku; Hosoi, Takuji; Shimura, Takayoshi; Watanabe, Heiji ^[1]

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1. Department of Material and Life Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

We have investigated the stability of amorphous germanium nitride (Ge{sub 3}N{sub 4}) layers formed by plasma nitridation of Ge(100) surfaces using x-ray photoelectron spectroscopy and atomic force microscopy. We have found that humidity in the air accelerates the degradation of Ge{sub 3}N{sub 4} layers and that under 80% humidity condition, most of the Ge-N bonds convert to Ge-O bonds, producing a uniform GeO{sub 2} layer, within 12 h even at room temperature. After this conversion of nitrides to oxides, the surface roughness drastically increased by forming GeO{sub 2} islands on the surfaces. These findings indicate that although Ge{sub 3}N{sub 4} layers have superior thermal stability compared to the GeO{sub 2} layers, Ge{sub 3}N{sub 4} reacts readily with hydroxyl groups and it is therefore essential to take the best care of the moisture in the fabrication of Ge-based devices with Ge{sub 3}N{sub 4} insulator or passivation layers.

• OSTI ID: 21013722
• Journal Information: Applied Physics Letters, Vol. 91, Issue 16; Other Information: DOI: 10.1063/1.2799260; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AIR
AMORPHOUS STATE
ATOMIC FORCE MICROSCOPY
CHEMICAL BONDS
FABRICATION
GERMANIUM NITRIDES
GERMANIUM OXIDES
HUMIDITY
HYDROXIDES
LAYERS
NITRIDATION
PASSIVATION
PLASMA
ROUGHNESS
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0273-0400 K
THIN FILMS
TIME DEPENDENCE
X-RAY PHOTOELECTRON SPECTROSCOPY