What is the difference between direct and indirect band gap semiconductors explain with reference to their application in device fabrication?

In a direct band gap semiconductor, the top of the valence band and the bottom of the conduction band occur at the same value of momentum. In an indirect band gap semiconductor, the maximum energy of the valence band occurs at a different value of momentum to the minimum in the conduction band energy.

What is the difference between direct and indirect bandgap semiconductors?

If the k-vectors are different, the material has an “indirect gap”. The band gap is called “direct” if the crystal momentum of electrons and holes is the same in both the conduction band and the valence band; an electron can directly emit a photon. Indirect bandgap materials include crystalline silicon and Ge.

Which of the following is a direct band gap semiconductor?

Examples for direct band gap semiconductor materials are gallium arsenide (GaAs), indium gallium arsenide (InGaAs), gallium nitride (GaN), aluminum nitride (AlN), cadmium sulfide (CdS), cadmium selenide (CdSe), cadmium tellurite (CdTe), zinc sulfide (ZnS), lead sulfide (PbS) and lead selenide (PbSe).

Which of the following is known as direct band gap semiconductors?

Compound semiconductors are also known as direct band gap semiconductors.

What is indirect band gap semiconductor example?

Examples for indirect band gap semiconductor materials are silicon (Si), germanium (Ge), aluminum arsenide (AlAs) and gallium phosphide (GaP).

Why direct band gap semiconductors are more suitable for light emitting applications?

In direct band gap semiconductors like gallium nitride most of these electrons are in the trough of the conduction band and may move to the valence band without any change in momentum from a phonon. It is more efficient that LEDs are made from direct semiconductors so that nothing else (phonons) is required.