Give a classification of semiconductors and write examples of each.

(N/A) Semiconductors are classified into elemental and compound semiconductors.
$(i)$ Elemental semiconductors: These are made of a single element. Examples: $Si$ and $Ge$.
$(ii)$ Compound semiconductors: These are formed by combining two or more elements. They are further classified as:
$(A)$ Inorganic: Examples include $CdS$,$GaAs$,$CdSe$,and $InP$.
$(B)$ Organic: Examples include anthracene and doped phthalocyanines.
$(C)$ Organic polymers: Examples include polypyrrole,polyaniline,and polythiophene.
Most currently available semiconductor devices are based on elemental semiconductors ($Si$ or $Ge$) and inorganic compound semiconductors. Since $1990$,devices using organic semiconductors and semiconducting polymers have been developed,marking the birth of polymer electronics and molecular electronics.