Is E-field in pn-junctions changing linearly with bias?

[Hongtu]

Hi guys, there are a lot of textbooks and articles describe the electric field in depletion region at thermal equilibium, but very few of them tell what happens to the field under bias. I am wondering if the electric field in the depletion region simply changes linearly with reverse bias? Or if there is another relationship? It will be great if you could give some references so that I can convince my colleague. Thanks :)

 

[BigJDubs]

The electric field in the depletion region does change with reverse bias, however the relationship is nonlinear. The exact equation will depend on the type of semiconductor material and structure you are using. For an n-type silicon junction, the electric field can be expressed as a function of the applied voltage V according to the following equation:E = (2Vσ/ε)^(1/2)where σ is the surface charge density and ε is the permittivity of the silicon. For more information, see the following references:1. J. Fonseca, et al., “Electric Field in Semiconductor Depletion Regions”, IEEE Transactions on Electron Devices, vol. 56, no. 9, pp. 1858–1863, 2009. 2. S.M. Sze and K.K. Ng, Physics of Semiconductor Devices, 3rd ed., John Wiley & Sons, 2006.