What is recombination lifetime in semiconductor?
A definition in semiconductor physics, carrier lifetime is defined as the average time it takes for a minority carrier to recombine. The process through which this is done is typically known as minority carrier recombination.
What is surface recombination?
Surface recombination can be defined as the product of surface recombination velocity and the difference in minority carrier concentrations between thermal equilibrium and at the surface, and surface recombination velocity depends on some intrinsic material parameters, such as the minority carrier diffusion length ( …
Which technique is used to overcome surface recombination?
To achieve optimal operation, surface recombination is reduced by a passivating or window layer that prevents minority carriers from reaching the surface.
What is front surface recombination?
The reduction of the number of dangling bonds, and hence surface recombination, is achieved by growing a layer on top of the semiconductor surface which ties up some of these dangling bonds. This reduction of dangling bonds is known as surface passivation.
What is the surface lifetime of surface recombination?
Recombination at the surfaces is typically described by a surface lifetime τ s, which includes the fundamental decay mode but ignores higher decay modes. τ s is a function of the surface recombination velocities S 1 and S 2, the cell width W and the minority carrier diffusivity D.
How do surface and bulk recombination affect the lifetime of carriers?
One surface has a high recombination and the other has a low recombination so S 1 = 0 and S 2 = ∞ The combination of the effects of surface and bulk recombination give the effective lifetime of carriers τ eff within a sample.
How to tune the surface recombination velocities?
For this purpose, the surface recombination velocities are tuned by applying various surface modifications. This enables to explore systematically the parameter space, to disentangle the contributions of surface and bulk recombination and to determine lower and/or upper bounds of the parameters.
What is the maximum possible decay time for surface recombination?
This value is significantly larger than the highest measured decay time (48 ns for the delam configuration) and shows a clear influence of the surface recombination on experimental data.