Chapter 7, Problem 12SAQ

Interpretation Introduction

Interpretation:

A semiconductor material is one whose electrical properties lies between insulator and conductors.

Example: germanium, silicon etc.

In terms of energy bands, semiconductors can be defined as those materials which have an empty conduction band and almost filled valence band with a very narrow energy gap (of the order of $1$. Electron volt).

Concept introduction:

This type semiconductor is obtained when traces of trivalent (like B) atom are added to a pure germanium crystal. In this case, the three valence electrons of boron atom form covalent bond with four surrounding germanium atoms but one bond is incomplete and gives the hole.

Trivalent atom is called acceptor impurity.

To determine:

With which element would you dope silicon to produce a p-type semiconductor?

(a) $Sb$ (b)$As\left(c\right)Ge\left(d\right)Ga$