COMEDK2017PhysicsSemiconductors
Identify the property which is not characteristic for a semi-conductor.
Options
- AAt a very low temperatures it behaves like an insulator.
- BAt higher temperatures two types of charge carriers will cauise conductivity.
- CThe charge carriers are electrons and holes in the valance band at higher temperatures.
- DThe semiconductor is electrically neutral.
Correct answer
A. At a very low temperatures it behaves like an insulator.
Step-by-step solution
A semiconductor acts like an insulator only at absolute temperature i.e. 0^ K . It is because the free electrons in the valence band of semiconductor will not carry enough thermal energy to overcome the forbidden energy gap at absolute zero. Hence, option (a) is not correct.