Adding gallium, boron, or indium to pure silicon or germanium will create a material with an excess of?

Answer: the excess material created is called "Hole".

Explanation: When the semiconductor such as silicon or germanium with four electrons in the outermost shell known as valence electron is added to either of electrons from indium, gallium or boron which has three valency electrons, a hole is created.

A hole which has positive charge is caused as a result of the movement of valence electrons from an atom to another atom.

A hole brings about conduction in semiconductor materials, (i. e when the free electrons with negative charge and holes with positive charge move in opposite direction in the semiconductor, conduction takes place).

Adding gallium, boron, or indium to pure silicon or germanium will create a material with an excess of holes which is called a p-type material.

Explanation:

gallium, boron or indium are elements with three valency electron, and they are called Acceptor impurities. When acceptor impurities are added to pure silicon, it is called dopping

dopping: This is the process by which impurities is added to semi conductors in order to alter its electrical conductivity. The impurities is called dopants.

Adding gallium, boron, or indium to pure silicon or germanium will create a material with an excess of holes which is called a p-type material.