Question: 1 -

Measurement of Hall coefficient in a semiconductor provides information on the,

Mass and concentration of charge carriers

Sign of charge carriers alone

Sign and concentration of charge carriers

Sign and mass of charge carriers

Answer:

Sign and concentration of charge carriers

Solution not available.

Question: 2 -

The carrier mobility in a semiconductor is 0.4 m²/V-s . Its diffusion constant at 300 K will be (in m²/s),

0.01

0.04

0.16

0.43

Answer:

0.01

Solution not available.

Question: 3 -

At very high temperature , the extrinsic semiconductors become intrinsic because

band to band transition dominates over impurity ionization

of drive-in diffusion of dopants and carriers

band to band transistion is balanced by impurity ionization

impurity ionization dominates over band to band transistion

Answer:

band to band transition dominates over impurity ionization

Solution:

At high temperature , thermal generated electron-hole pairs start dominating impurity ionization.

Question: 4 -

The increasing temperature , the electrical conductivity would :

Increase in metals as well as in intrinsic semiconductors

Increase in metals but decrease in instrinsic semiconductors

Decrease in metals as well as in intrinsic semiconductors

Decrease in metals but increase in intrinsic semiconductor

Answer:

Decrease in metals but increase in intrinsic semiconductor

Solution:

In metals , with increasing temperature conductivity will decrease while in intrinsic semiconductor conductivity increase because of electron-hole pair generation.

Question: 5 -

The minority carrier life-time and diffusion constant in a semiconducting material are 100 microsecond and 100cm²/s respectively . The diffusion length of the carrier is,

0.01cm

0.0141cm

1cm

0.1cm

Answer:

0.1cm

Solution not available.