Microwave Diodes (Varactor Diode, p-i-n Diode, IMPATT Diode, TRAPATT Diode, BARITT Diode, etc.)

Abstract

Microwave diodes are used to provide amplification, oscillation and other functions at microwave frequencies. They have a large bandwidth, therefore more information can be transmitted in microwave frequency range. It is the current trend to use microwaves more and more in long distance communication such as telephony, TV network, space communication, radars, microwave ovens etc. Therefore in this chapter, the Varactor diode; its construction, characteristics, performance and applications are presented, different types of semiconductor photodiodes are classified, and the IMPATT diode, TRAPATT diode and BARITT diode are elaborated along with their operation, performance and applications. The construction, operational characteristics and applications of p-n photodiodes, p-i-n photodiode, avalanche photodiode, and mid-infrared photodiodes are described. The transferred electron mechanism, valleys in conduction band and dependence of electron velocity on electric field are discussed. The Gunn diode: its fabricational materials, dielectric relaxation time etc. are given. The Dovett diode is also discussed. Minute insight into the various topics are given through solved numerical and theoretical examples. Review questions, numerical problems and objective type questions are also given with their answers.