Energy gap of semiconductor

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Purpose:-

Determining the semiconductor power gap provided.

Apparatus:-

DC source, Milli-ammeter, Voltmeter, PN diode, connecting cables.

Circuit diagram:-




Opinion:-

The semiconductor diode has a power space. It can be successfully measured in the case of reverse currents as only a small amount of current flow of small flow. Measured by eV unit. (1ev is equal to (1.602 × 1019) .The power gap between the top of the valence band and the bottom of the drive belt is called the bandgap. It is about 0.7V Germanium and 1.1 for Silicon.


Process: -

1. Connect the circuit as shown in fig.

2. Immerse the PN junction diode in a paraffin test tube full of paraffin.

3. Start heating the bathwater and note that the temperature reaches 70C

4. Place the thermometer in the water bath and record the temperature.

5. As the temperature drops in all 50 records of current falls and electrical power up to room temperature.

6. The graph of the plot of logIs v / s (1000 / T) and determine the line drop.

Tabular column:-



Calculation:-

Semiconductor power gap Eg = slope ÷ 5.0 36eV.


Nature of Graph:-



Result: -

The semiconductor power gap is Eg = ______ eV

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