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A si p -n junction 10-2 cm2 in area has nd = 1015 cm-3 doping on the n side. calculate the junction capacitance with a reverse bias of 10 v.

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Answer:

Here are the steps on how to calculate the junction capacitance of a Si p-n junction with a reverse bias of 10 V:

1. Calculate the depletion width.

The depletion width is the width of the region in which there are no free charge carriers. It can be calculated using the following formula:

```

W = √(2εεoV/qN)

```

where:

* W is the depletion width in meters

* ε is the permittivity of silicon (8.854 × 10-12 F/m)

* εo is the permittivity of free space (8.854 × 10-12 F/m)

* V is the reverse bias voltage in volts

* q is the elementary charge (1.602 × 10-19 C)

* N is the doping concentration in cm-3

In this case, the reverse bias voltage is 10 V and the doping concentration is 1015 cm-3. Plugging these values into the formula, we get:

W = √(2 × 8.854 × 10-12 F/m × 8.854 × 10-12 F/m × 10 V / 1.602 × 10-19 C × 1015 cm-3) = 1.249 μm

2. Calculate the junction capacitance.

The junction capacitance is the capacitance of the depletion region. It can be calculated using the following formula:

```

C = εA/W

```

where:

* C is the junction capacitance in Farads

* ε is the permittivity of silicon (8.854 × 10-12 F/m)

* A is the area of the junction in m2

* W is the depletion width in meters

In this case, the area of the junction is 10-2 cm2 and the depletion width is 1.249 μm. Plugging these values into the formula, we get:

```

C = 8.854 × 10-12 F/m × 10-2 cm2 / 1.249 μm = 7.12 pF

```

Therefore, the junction capacitance of a Si p-n junction with a reverse bias of 10 V is 7.12 pF.

Step-by-step explanation:

User Sebastian Barth
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