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Semiconductor Physics, Quantum Electronics & Optoelectronics. 2012. V. 15, N 3. P. 218-222.
Peculiarities of thermoannealing in n-Si and n-Ge crystals
with oxygen impurity
1V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine,
45, prospect Nauky, 03680 Kyiv, Ukraine Abstract. Investigated in this work were changes in the concentration of charge carriers ne and their mobilities , which occur under the influence of thermoannealing of and crystals grown by the Czochralski method. Thermoannealing of samples was carried out both at 450 °C and 650 °C. The results of the influence of two-stage (combined) thermoannealing have been presented. In the first series of experiments, the annealing was performed at 450 °C with varied duration (from 5 to 45 h) at the beginning, and then it was carried out for 40 hours at 650 °C. The second series of experiments was as follows: the annealing at 450 °C for 45-hour duration, then the annealing at 650 °C, which was carried out for various periods of time (5, 10, 20, 45, 66 hours). The observations for changes of ne and were carried out both at the temperature 300 and 77 K. It is ascertained that changing the main parameters (ne and μ) in n-Ge <As> heavily doped single crystals, as a result of the series of thermoannealings (duration 30 min in each case) within the temperature range from 540 to 900 °C, is non-monotonous due to transformation of the thermodonors TD-I into TD-II .
Keywords: silicon, germanium, oxygen, thermoannealing, thermodonor, the Hall effect, carrier concentration, mobility.
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