Reverse bias applied on a junction diode: (A) raises the potential barrier (B) increases majority charge carrier current (C) lowers the potential barrier (D) increases the temperature of junction

A junction diode is a two-terminal electronic device made of semiconductor material. It typically consists of a P-type semiconductor (with majority carriers being holes) and an N-type semiconductor (with majority carriers being electrons). When these materials are brought into contact, a junction is formed, known as the P-N junction. The P-N junction has a potential barrier (also known as a depletion region) due to the migration of majority carriers from their respective sides to the other side, leaving behind charged ions.

There are two types of biasing in junction diodes: forward bias and reverse bias. Forward bias occurs when the P-type material is connected to the positive terminal and the N-type material is connected to the negative terminal of an external voltage source. In this case, the applied potential difference reduces the potential barrier of the junction, allowing majority charge carriers to flow across the junction. Reverse bias, on the other hand, is when the P-type material is connected to the negative terminal and the N-type material is connected to the positive terminal of the external voltage source. In this case, the potential difference increases the potential barrier and prevents majority charge carriers from crossing the junction. As a result, the current flow in the diode is minimal in reverse bias.

Now, let's analyze the given options based on the understanding of the working of a junction diode under reverse bias: (A) raises the potential barrier: As discussed earlier, applying reverse bias increases the potential barrier, preventing majority charge carriers from crossing the junction. So, this statement is correct. (B) increases majority charge carrier current: In reverse bias, the potential barrier prevents the majority charge carriers from crossing the junction, which essentially means the majority charge carrier current decreases. Thus, this statement is incorrect. (C) lowers the potential barrier: This statement is the opposite of what occurs under reverse bias, which increases the potential barrier. Therefore, this statement is incorrect. (D) increases the temperature of junction: The temperature of the junction is not directly related to the reverse bias applied to the diode. It may increase due to the power dissipation in the diode, but it is not a direct effect of reverse bias itself. So, this statement is also incorrect. Based on the analysis, option (A) is the correct answer.