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Fichas del conjunto (6)
- 1Q .1 State and explain LAW OF MASS ACTION ?ANS:
The product of equilibrium concentration of electrons and holes is equal to intrinsic carrier cocentration
no . po = ni^2 - 2Q .2 State and explain SEMICONDUCTOR MATERIALS ?ANS :
> having electrical conductivity btwn that of conductors and insuators
> conductivity range - 10^-8 ohm^-1cm^-1 to 10^-3 ohm^-1 cm^-1
> conductivity can be varied by doping
> conductivity of doped sc remains constant over a wide range of temperature - 3Q .3 CLASSIFICATION OF SEMICONDUCTORS ?ANS :
> elemental and compound
> intrinsic and extrinsic sc
> direct and indirect bandgap - 4Q .4 DEFINE ELEMENTAL SEMICONDUCTOR WITH SUITABLE EXAMPLESANS :
SC CONSIST OF SINGLE SPECIES OF ATOM ARE CALLED ELEMENTAL SC
Eg : Si , Ge - 5Q .5 ADVANTAGES OF Si OVER Ge ?> abudant in nature
> easy process of purification
> can be operated at high temperature
> fabrication is simple - 6Q . 6 DEFINE COMPOUND SEMICONDUCTOR WITH SUITABLE EXAMPLESANS :
SC Constituted by two or more elements are called compound
3 & 5 compounds : consist of elements from group 3 and 5
Eg : ALP , GaAs , GaP
USES : LED's
2 & 4 compounds : consist of elements from group 2 and 4
Eg : ZnS, InSb, CdSe
USES: Zns >fluroscent materals in TV
InSb, CdSe > light detectors can be made