Question

How many electrons from the dopant form bonds with neighbouring silicon atoms?

Options

• No electrons form bonds with neighbouring silicon atoms.

• Four electrons form bonds with four neighbouring silicon atoms.

• Five electrons form bonds with four neighbouring silicon atoms.

• One electron forms bonds with four neighbouring silicon atoms.

Answer 1

Four of the dopant atom’s five valence electrons form bonds with four neighbouring silicon atoms. The fifth electron remains weakly bound to its parent atom.