Journal article
Trapping effects and acoustoelectric current saturation in ZnO single crystals
Measurements of current-voltage characteristics for ZnO single crystals at temperatures between 77 and 640 °K are reported. Because of the buildup of an intense acoustic flux, a strong current saturation sets in when the trap-controlled electron drift velocity is equal to the velocity of sound. The temperature dependence of the saturated current is discussed in terms of a trapping model which includes nonlinear trapping effects.
Our results indicate the presence of a shallow-donor level with an ionization energy of 50 meV and a deep-donor level approximately 230 meV below the conduction-band edge. The capture cross section for the shallow donors is determined to be about 5 × 10-12 cm2 at 100 °K.
Language: | English |
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Year: | 1970 |
Pages: | 3234-3248 |
ISSN: | 05562805 , 1550235x , 10980121 and 24699950 |
Types: | Journal article |
DOI: | 10.1103/PhysRevB.2.3234 |