O'Reilly logo

Pulse and Digital Circuits by Manmadha Rao G., Rama Sudha K., Venkata Rao K.

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

16.4 TUNNEL DIODES

In a pn diode, the width of the depletion layer varies inversely as the square root of impurity concentration. Thus, the smaller the impurity concentration (doping), the larger the depletion region and vice-versa. The impurity concentration, in a pn junction diode is of the order of 1 in 108. With this impurity concentration, the width of the depletion layer is typically 5 microns (5 × 10−6 m). If on the other hand, if this impurity concentration is increased to 1 in 103, the width of the depletion region may be as small as 0.01 microns (0.01 × 10−6 m) i.e., the depletion layer becomes very thin. Thus, if a pn junction diode is formed with such high impurity concentrations, the barrier becomes very thin. When the depletion ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required