Breakdown Voltage of PN Junctions: P+-N vs. N+-P

[Fermi_98]

Hiya,
Being a computer science and eng first year student, just trying to understand one artical regarding Breakdown voltage of a pn junction.Could anybody explain me, which diode out of the following have higher breakdown voltage if they have same design parameters such as doping and thickness and why ?
1. p+-n diode
2. n+-p diode

 

[ctjen]

Hiya,
Being a computer science and eng first year student, just trying to understand one artical regarding Breakdown voltage of a pn junction.Could anybody explain me, which diode out of the following have higher breakdown voltage if they have same design parameters such as doping and thickness and why ?
1. p+-n diode
2. n+-p diode

Can you clarify your diode notation. It seems ambiguous.

Chris

 

[Fermi_98]

I suppose, i should have rather written as p+nn+. If you are familiar with power rectifiers, it is quite common notation used in there, to denote the high voltage rectifier.
High voltage rectifiers are fabricated in silicon which is either n-type or p-type.

1. "p" refers to quantity of the p-type semiconductor for instance boron etc. The + sign shows that boron atoms concentration, we are talking is in the order of greater then 1e18 cm-3 .This much of the boron atom concentration is diffused into the n type silicon to make a rectifier. It is therefore denoted by p+n.

2. like wise "n " refers to n-type semiconductor for instance phosphorous etc. Again, when the doping concentration is very high, we denote it by n+.

so same is applicable to other type of the rectifier for instance n+pp+.