In my previous article, I wrote up to classification of Extrinsic Semiconductor. There are two types of Extrinsic semiconductor. 1. n-type and 2. p-type semiconductor.
What is n-type semiconductor?
Silicon that has been doped with a pentavalent impurity is called n-type semiconductor. Since the free electron outnumber the whole is an n-type semiconductor, the free electrons are called the majority carriers and the holes are called the minority carriers. Because of the free electrons move to the left and the holes are move to the right.
What is p-type semiconductor?
Silicon that has been doped with trivalent impurity is called p-type semiconductor. Since the free holes outnumber free electrons, the holes are referred to as the majority carriers and the free electrons are known as minority carriers. Because of the applied voltage, the free electrons move to the left and the holes are move to the right.
As I described in my this review and in the previous one are most important part for basic knowledge.
Diode is another important element for a electrical circuit. A diode can change the current flow path or it can stop also. Mainly, a diode has two region. 1. Forward bias and 2. Reverse bias. In forward bias, the holes are close and electron can flow without resistance. But in the reverse bias, the conductivity is opened and current flow in the resistance. In a half wave rectifier, one diode is use for current flow, but in a full wave rectifier, two diodes are required. Here, it is good to know that, “When you troubleshoot a circuit that contains a silicon diode that is supposed be forward biased, a diode voltage measurement much greater that 0.7V, means that the diode has failed and is in fact open”.
The half wave rectifier:
The ac source produces a sinusoidal voltage. Assuming an ideal diode, the positive half cycle of source voltage will forward bias the diode. Since the switch is closed, the positive half cycle of source voltage will appear across the load resister.