00:01
The total current density in a silicon semiconductor is constant and equals to minus 10 ampere per centimeter square.
00:14
The total current is composed of a whole drift current, diffusion current and electron diffusion current, assuming the electron concentration is given by nx equal.
00:31
2 into 10 raised to the power of 15, e raised to the power minus x by l, centimeter raised to the power minus 3, where l is 15 micrometer, the electron diffusion coefficient, diffusion coefficient d n equals 27 centimeters square per second, and the whole mobility, mupi equals 420 centimeters square per volt second at the temperature 300 kelvin.
01:16
Then find the electron diffusion current density for x greater than 0.
01:32
And the whole drift current density, current density for x greater than 0.
01:44
And lastly, the required electric field for x greater than 0.
01:53
As the total current density is minus 10 ampere per centimeter square, j total is minus 10 ampere per centimeter square, this is also equals to the current density for drift plus diffusion the electron concentration is given where l is 15 micrometer first to find the electron diffusion current density i diffusion equals e into dn into dn by d x that is the differentiation of n with respect to x.
02:35
Here e is the charge on electron.
02:38
Substituting the values, 1 .602 into 10 raise to the power minus 19, multiply 27 into.
02:46
On differentiation, we get minus 1 by l into 2 into 10 raised to the power 5 into e raised to the power minus x by l...