CHEMICAL EFFECTS ON GRAIN BOUNDARY MIGRATION IN Si AND Ge.
Atomic mobility is very low in elemental semiconductors in the solid state. Consequently in contrast to metals, amorphous silicon can be made by CVD and both crystallization and grain growth are sluggish processes. Heavy doping with P or As enhances boundary mobility at elevated temperatures (T grea...
| Main Authors: | , |
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| Format: | Journal article |
| Language: | English |
| Published: |
Japan Inst of Metals
1986
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| Summary: | Atomic mobility is very low in elemental semiconductors in the solid state. Consequently in contrast to metals, amorphous silicon can be made by CVD and both crystallization and grain growth are sluggish processes. Heavy doping with P or As enhances boundary mobility at elevated temperatures (T greater than 0. 7T//m) despite the resistance resulting from segregation. At low temperatures (T Approximately 0. 4T//m) grain boundary mobility is enhanced by concurrent alloying. This process may involve liquid films or be purely solid state. It is also found that crystallization kinetics are affected by stress. These several effects can be understood in terms of (a) a solute effect on the activation energy for boundary migration, (b) the additional effects of misfit resulting from alloying by grain boundary or liquid diffusion and (c) the excess volume at grain boundaries. |
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