Schottky Barrier Diode, Schottky Transistor

Schottky Barrier Diode

No PN Junctions are allowed to form between the metal and silicon layers, and the metal contacts must be ohmic. Making ohmic contacts is the function of the N+ Diffusion region. On the other hand,. A metal Semiconductor diode is said to have been created if Aluminium is directly Deposited on the N-type silicon. The V-I Characteristics of this type of metal semiconductor diode Junction are Identical to those of a typical PN Junction.

A Schottky barrier diode’s cross section and symbol are Depicted in figure. Figured contacts 1 and 2 are Schottky Barriers and ohmic contacts, Respectively. A barrier was created for the flow of Conducting Electrons from Semiconductor to metal. By the contact potential between the Semiconductor and the metal. This barrier is lowered and the flow of electrons from Semiconductor to metal, where there are Abundant Electrons, is Permitted when the Junction is forward Biassed.

In a PN junction diode, the minority carriers carry the conduction current, but there is a noticeable time delay between the ON and OFF states. Minority carriers carry the conduction current in Schottky diodes. This is because the minority carriers that are stored in the junction must be completely removed. Due to its ability to flow electrons from N-type silicon into aluminium almost immediately at the contact surface, where they can mix with free electrons, the Schottky barrier diode has an advantage over other devices. Another benefit of this diode is that its forward voltage is lower (approximately 0.4V). As a result, it can be used for clamping and detection in microwave integrated circuits and high frequency applications.

Schottky Transistor

The figure shows the Cross-sectional view of a Transistor with a Schottky barrier diode clamped between its base and Collector regions. Figure depicts the equivalent circuit as well as a symbol for the Schottky transistor. As shown in the figure, the Schottky diode is created by Allowing Aluminium to be Metallized on the base lead, which comes into contact with the N-type Collector region.

The voltage at the collector C drops as the base current is increased to saturate the transistor, which causes the diode Ds to conduct. The base to collector voltage drops to 0.4V, which is lower than a silicon base-collector junction’s cut-in voltage. Transistor saturation is prevented as a result.