Classification of Crystal Diodes 1

1、 According to the construction classification, semiconductor diodes mainly rely on PN junctions to operate. The point contact type and Schottky type, which are inseparable from the PN junction, are also included in the scope of general diodes. Including these two models, based on the characteristics of PN structure surface construction, crystal diodes are classified as follows:

1. Point contact diode is formed by pressing a metal needle onto a single crystal of germanium or silicon material, and then using the current method. Therefore, its PN junction has a small electrostatic capacity and is suitable for high-frequency circuits. However, compared to surface junction diodes, point contact diodes have poor forward and reverse characteristics, and therefore cannot be used for high currents and rectification. Due to its simple structure, it is inexpensive. For general applications such as detection, rectification, modulation, mixing, and limiting of small signals, it is a widely used type.