If `n_(e)` and `n_(h)` are the number of electrons and holes in a semiconductor heavily doped with phosphorus, then

if n_e aand n_h are the no. of electrrons and holes in a semiconductor heavily doped with phosphorous , then

Let n_(e) and n_(b) are the number density of electrons and holes in extrinsic semiconductor then-

If n_(e) and n_(h) be the number of electrons and drift velocity in a semiconductor. When the temperature is increased

A pure semiconductor germanium or silicon, free of every impurity is called intrinsic semiconductor. A room temperature, a pure semiconductor has a very small number of current carriers (electrons and holes). Hence, its conductivity is low. When the impurity atoms of valence five or three are doped in a pure semiconductor, we get repectively n-type ot p-type extrinsic semiconductor. In case of a doped semiconductor. n_(e)n_(h)=n_(i)^(2) , where n_(e) and n_(h) are the number density of electrons and holes respectively and n_(i) is the number density of intrinsic charge carriers in a pure semiconductor. The conductivity of extrinsic semiconductor is much higher than that of intrinsic semiconductor. (i) Name two materials to be doped in pure semiconductor of silicon to get p-type semiconductor n-type semiconductor. (ii) What do you learn from the above study?

If N_(P) and N_(e) be the numbers of holes and conduction electrons in an extrinsic semiconductor, then

Let n_(p) and n_(e) , be the numbers of holes and condution electrons in an intrinsic semiconductor