Introduction:
A Schottky diode is a type of diode that is formed by the combination of a metal and a semiconductor material. It has several advantages over an equivalent p-n junction diode, including faster switching speeds. In this response, we will explain why a Schottky diode can be switched off much faster than a p-n junction diode due to the absence of recombination of charges.

Explanation:

1. Operation of a Schottky Diode:
A Schottky diode is formed by the junction of a metal (usually a metal with a low work function, such as aluminum or platinum) and a semiconductor material (usually n-type silicon). The metal acts as the anode and the semiconductor acts as the cathode of the diode. When a positive voltage is applied to the anode with respect to the cathode, current can flow through the diode. When a negative voltage is applied, the diode is in the "off" state, and no current can flow.

2. Absence of Recombination of Charges:
In a p-n junction diode, when the diode is forward biased (positive voltage applied to the p-side and negative voltage applied to the n-side), electrons from the n-side and holes from the p-side move towards the junction. At the junction, the electrons and holes recombine, resulting in the release of energy in the form of light or heat. This recombination process takes some time.

In a Schottky diode, since there is no p-n junction, there is no recombination of charges at the junction. When the diode is forward biased, electrons from the metal anode move towards the semiconductor cathode, and holes from the semiconductor move towards the metal. These charges quickly move away from the junction, resulting in a fast switching off process.

3. Faster Switching Speed:
The absence of recombination of charges in a Schottky diode allows it to switch off much faster than a p-n junction diode. The charges in a Schottky diode quickly move away from the junction, leading to a rapid decrease in the forward current. In contrast, in a p-n junction diode, the recombination process takes some time, resulting in a slower decrease in the forward current.

Conclusion:
The absence of recombination of charges at the junction of a Schottky diode enables it to switch off much faster than an equivalent p-n junction diode. This makes Schottky diodes suitable for high-speed switching applications, where fast turn-off times are required.