shottky diode
ELECTROTECH99
30.10.11 21:49
BTS Electrotechnique ANGLAIS Session 1999
WHAT IS A SCHOTTKY DIODE?
The Schottky diode is an important device which is widely used in radio-frequency (RF) applications. It possesses many similarities to the point-contact diode. In fact many of the early devices were made in the same way as a point-contact diode, although today's devices are made with totally different manufacturing techniques.
Unlike conventional semiconductor diodes, which consist of a PN junction, the Schottky diode is made from a metal semiconductor junction. This offers a number of advantages in some circumstances as the diode has a very low forward-voltage drop, and secondly it has a very fast switching speed. Both of these properties make it ideal for many RF applications as well as giving it uses in many other areas, as we shall see.
Characteristics.
The Schottky diode is what is called a majority carrier device. This gives it tremendous advantages in terms of speed. By making the devices small, the normal RC (resistancecapacitance) type time constants can be reduced, making the Schottky diode an order of magnitude faster than the conventional PN diodes. This factor is the prime reason why they are so popular in RF applications.
The Schottky diode also has a much higher current density than an ordinary PN junction. This means that forward-voltage drops are lower, making these diodes ideal for use in powerrectification applications. The main drawback of the diode is found in the level of its reverse current, which is relatively high. For many uses this may not be a problem, but it is a factor which is worth watching when using Schottky diodes in more exacting applications.
Variety of Applications.
The Schottky diode is used in a wide variety of applications. It can naturally be used as a general-purpose rectifier. However, in terms of RF applications, it is particularly useful because of its high switching speed and
30.10.11 21:49
BTS Electrotechnique ANGLAIS Session 1999
WHAT IS A SCHOTTKY DIODE?
The Schottky diode is an important device which is widely used in radio-frequency (RF) applications. It possesses many similarities to the point-contact diode. In fact many of the early devices were made in the same way as a point-contact diode, although today's devices are made with totally different manufacturing techniques.
Unlike conventional semiconductor diodes, which consist of a PN junction, the Schottky diode is made from a metal semiconductor junction. This offers a number of advantages in some circumstances as the diode has a very low forward-voltage drop, and secondly it has a very fast switching speed. Both of these properties make it ideal for many RF applications as well as giving it uses in many other areas, as we shall see.
Characteristics.
The Schottky diode is what is called a majority carrier device. This gives it tremendous advantages in terms of speed. By making the devices small, the normal RC (resistancecapacitance) type time constants can be reduced, making the Schottky diode an order of magnitude faster than the conventional PN diodes. This factor is the prime reason why they are so popular in RF applications.
The Schottky diode also has a much higher current density than an ordinary PN junction. This means that forward-voltage drops are lower, making these diodes ideal for use in powerrectification applications. The main drawback of the diode is found in the level of its reverse current, which is relatively high. For many uses this may not be a problem, but it is a factor which is worth watching when using Schottky diodes in more exacting applications.
Variety of Applications.
The Schottky diode is used in a wide variety of applications. It can naturally be used as a general-purpose rectifier. However, in terms of RF applications, it is particularly useful because of its high switching speed and