Основы физики и химии полупроводников - 48 стр.

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ɦɨɝɭɬ ɩɪɨɧɢɤɚɬɶ ɧɚ ɡɧɚɱɢɬɟɥɶɧɭɸ ɝɥɭɛɢɧɭ, ɢɫɩɵɬɵɜɚɹ ɭɩɪɭɝɨɟ ɪɚɫɫɟɹɧɢɟ,
ɢ ɜɦɟɫɬɟ ɫ ɭɩɪɭɝɨ ɪɚɫɫɟɹɧɧɵɦɢ ɷɥɟɤɬɪɨɧɚɦɢ ɬɟɪɹɸɬ ɱɚɫɬɶ ɷɧɟɪɝɢɢ ɧɚ
ɜɨɡɛɭɠɞɟɧɢɟ ɚɬɨɦɨɜ ɜɟɳɟɫɬɜɚ, ɜ ɪɟɡɭɥɶɬɚɬɟ ɱɟɝɨ ɜɨɡɧɢɤɚɟɬ ɪɟɧɬɝɟɧɨɜɫɤɨɟ
ɢɡɥɭɱɟɧɢɟ ɢ ɷɦɢɫɫɢɹ ɜɬɨɪɢɱɧɵɯ ɷɥɟɤɬɪɨɧɨɜ (ɚ ɬɚɤɠɟ Ɉɠɟ-ɷɥɟɤɬɪɨɧɨɜ).
ɉɨɫɤɨɥɶɤɭ ɷɧɟɪɝɢɹ ɜɬɨɪɢɱɧɵɯ ɷɥɟɤɬɪɨɧɨɜ ɧɟɜɟɥɢɤɚ (ɩɨɪɹɞɤɚ 10 ɷȼ), ɬɨ
ɜɬɨɪɢɱɧɵɟ ɷɥɟɤɬɪɨɧɵ, ɨɛɪɚɡɭɸɳɢɟɫɹ ɧɚ ɡɧɚɱɢɬɟɥɶɧɨɣ ɝɥɭɛɢɧɟ,
ɪɟɤɨɦɛɢɧɢɪɭɸɬ ɫ ɢɨɧɢɡɢɪɨɜɚɧɧɵɦɢ ɚɬɨɦɚɦɢ. Ɉɛɥɚɫɬɶ ɨɛɴɟɤɬɚ, ɤɨɬɨɪɚɹ
ɞɚɟɬ ɷɮɮɟɤɬ ɜɬɨɪɢɱɧɨɣ ɷɥɟɤɬɪɨɧɧɨɣ ɷɦɢɫɫɢɢ, ɢɦɟɟɬ ɝɥɭɛɢɧɭ ɦɟɧɟɟ 500 Å
ɢ ɞɢɚɦɟɬɪ, ɥɢɲɶ ɧɟɦɧɨɝɨ ɩɪɟɜɵɲɚɸɳɢɣ ɞɢɚɦɟɬɪ ɷɥɟɤɬɪɨɧɧɨɝɨ ɡɨɧɞɚ.
ɍɩɪɭɝɨ ɪɚɫɫɟɹɧɧɵɟ ɷɥɟɤɬɪɨɧɵ ɢɫɩɭɫɤɚɸɬɫɹ ɝɨɪɚɡɞɨ ɛɨɥɶɲɟɣ ɨɛɥɚɫɬɶɸ
ɨɛɴɟɤɬɚ, ɪɚɡɦɟɪ ɤɨɬɨɪɨɣ ɡɚɜɢɫɢɬ ɨɬ ɪɹɞɚ ɮɚɤɬɨɪɨɜ, ɧɨ ɨɛɵɱɧɨ ɝɥɭɛɢɧɚ ɧɟ
ɩɪɟɜɨɫɯɨɞɢɬ 1000 Å. Ɍɚɤɢɦ ɨɛɪɚɡɨɦ, ɢɡɨɛɪɚɠɟɧɢɟ ɜɨ ɜɬɨɪɢɱɧɵɯ
ɷɥɟɤɬɪɨɧɚɯ ɞɨɥɠɧɨ ɢɦɟɬɶ ɝɨɪɚɡɞɨ ɥɭɱɲɟɟ ɪɚɡɪɟɲɟɧɢɟ, ɱɟɦ ɢɡɨɛɪɚɠɟɧɢɟ ɜ
ɭɩɪɭɝɨ ɪɚɫɫɟɹɧɧɵɯ (ɨɬɪɚɠɟɧɧɵɯ) ɷɥɟɤɬɪɨɧɚɯ. Ɋɚɡɪɟɲɟɧɢɟ ɜɨ ɜɬɨɪɢɱɧɵɯ
ɷɥɟɤɬɪɨɧɚɯ ɜ ɫɨɜɪɟɦɟɧɧɵɯ ɩɪɢɛɨɪɚɯ ɩɪɢɦɟɪɧɨ ɫɨɨɬɜɟɬɫɬɜɭɟɬ ɩɨɩɟɪɟɱɧɢɤɭ
ɷɥɟɤɬɪɨɧɧɨɝɨ ɡɨɧɞɚ ɢ ɦɨɠɟɬ ɛɵɬɶ ɨɤɨɥɨ 100 Å. Ɋɚɡɪɟɲɟɧɢɟ ɜ ɭɩɪɭɝɨ
ɪɚɫɫɟɹɧɧɵɯ ɷɥɟɤɬɪɨɧɚɯ ɡɧɚɱɢɬɟɥɶɧɨ ɯɭɠɟɨɤɨɥɨ 1000 Å.
Ɇɟɯɚɧɢɡɦ ɮɨɪɦɢɪɨɜɚɧɢɹ ɤɨɧɬɪɚɫɬɚ, ɨɛɭɫɥɨɜɥɟɧɧɨɝɨ ɬɨɩɨɝɪɚɮɢɟɣ
ɩɨɜɟɪɯɧɨɫɬɢ ɨɛɪɚɡɰɚ, ɜɨ ɜɬɨɪɢɱɧɵɯ ɢ ɨɬɪɚɠɟɧɧɵɯ ɷɥɟɤɬɪɨɧɚɯ ɩɨɹɫɧɹɟɬɫɹ
ɫɥɟɞɭɸɳɢɦ ɪɢɫɭɧɤɨɦ. ɇɚ ɪɢɫ. 29, ɚ ɩɪɢɜɨɞɢɬɫɹ ɫɥɭɱɚɣ, ɤɨɝɞɚ ɧɚ ɫɟɬɤɭ
ɞɟɬɟɤɬɨɪɚ ɩɨɞɚɟɬɫɹ ɨɬɪɢɰɚɬɟɥɶɧɵɣ ɩɨɬɟɧɰɢɚɥ (–50 ȼ), ɡɚɩɢɪɚɸɳɢɣ ɬɨɤ
ɦɚɥɨɷɧɟɪɝɟɬɢɱɧɵɯ ɜɬɨɪɢɱɧɵɯ ɷɥɟɤɬɪɨɧɨɜ, ɧɨ ɫɥɚɛɨ ɜɥɢɹɸɳɢɣ ɧɚ ɛɵɫɬɪɵɟ
ɨɬɪɚɠɟɧɧɵɟ ɷɥɟɤɬɪɨɧɵ. Ɇɚɤɫɢɦɚɥɶɧɵɣ ɫɢɝɧɚɥ ɜ ɞɟɬɟɤɬɨɪɟ ɞɚɸɬ
ɷɥɟɤɬɪɨɧɵ, ɨɬɪɚɠɟɧɧɵɟ ɨɬ ɝɪɚɧɟɣ, ɪɚɫɩɨɥɨɠɟɧɧɵɯ ɩɨɞ ɩɪɹɦɵɦ ɭɝɥɨɦ ɤ
ɞɟɬɟɤɬɨɪɭ. ɂɡɨɛɪɚɠɟɧɢɟ ɧɚ ɷɤɪɚɧɟ ɛɭɞɟɬ ɨɱɟɧɶ ɤɨɧɬɪɚɫɬɧɵɦ, ɩɨɫɤɨɥɶɤɭ
ɝɪɚɧɢ, ɪɚɫɩɨɥɨɠɟɧɧɵɟ ɩɨɞ ɨɬɪɢɰɚɬɟɥɶɧɵɦ ɭɝɥɨɦ ɤ ɞɟɬɟɤɬɨɪɭ, ɧɟ
ɩɪɨɫɦɚɬɪɢɜɚɸɬɫɹ ɜɨɨɛɳɟ.
Ɋɢɫ. 29.Ɇɟɯɚɧɢɡɦ ɮɨɪɦɢɪɨɜɚɧɢɹ ɤɨɧɬɪɚɫɬɚ: ɚɜ ɨɬɪɚɠɟɧɧɵɯ ɷɥɟɤɬɪɨɧɚɯ;
ɛɫɦɟɲɚɧɧɨɟ ɢɡɨɛɪɚɠɟɧɢɟ ɜ ɨɬɪɚɠɟɧɧɵɯ ɢ ɜɬɨɪɢɱɧɵɯ ɷɥɟɤɬɪɨɧɚɯ:
Ⱦɞɟɬɟɤɬɨɪ (ɤɨɥɥɟɤɬɨɪ) ɷɥɟɤɬɪɨɧɨɜ; ɋɫɟɬɤɚ ɞɟɬɟɤɬɨɪɚ; 1 – ɩɚɞɚɸɳɢɣ ɥɭɱ
ɷɥɟɤɬɪɨɧɨɜ; 2 – ɨɬɪɚɠɟɧɧɵɟ ɷɥɟɤɬɪɨɧɵ; 3 – ɜɬɨɪɢɱɧɵɟ ɷɥɟɤɬɪɨɧɵ
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