a group 14 element is to be converted into n type semiconductor by doping it with a suitable impurity. To which group should this impurity belong

question : a group 14 element is to be converted into n type semiconductor by doping it with a suitable impurity. To which group should this impurity belong ?

key points to answer this question : first of all you have to remember that n type semiconductor means there is excess of electrons and due to this excess of electrons the n type semiconductor contains negative charge on it. hence the impurities must be from higher group.

solution : N type semiconductor means there is excess of electrons in this type of semiconductor , and as we know that due to presence of electrons conductivity is done hence N type of semiconductor shows high conductivity due to presence of these excess of electrons.

Hence a 14 group elements should be doped with the 15 group elements , because 15th group elements will create excess of electrons when they doped with 14 group elements. example : arsenic and phosphorus impurities mixed with 14th group elements will create n type semiconductor.