Temperature variation of resistance of a semiconductor

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Purpose: -

Study the variability of semiconductor temperatures.

Apparatus:-

DC source, milli-ammeter, voltmeter PN diode, thermometer, beaker, electric heater, connecting cables.

Theory:-



A semiconductor is a temperature-sensitive device with a negative coefficient of temperature resistance.it is because the valence electron jumps into the conduction state.

Process: -

1. The connection is made as shown in the picture.

2. Set a permanent DC source.

3. Heat water to 80 degrees

4. In every 5 falls

5. Plot graph of R v / s T & log R v / s 1 / T.

Tabular column:-




α = -2.303 × logR1-logR2 / T2-T1

Result: -

Note that as the temperature increases resistance decreases.

Value of temperature co-efficient is ____

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