Learning Forum

[HAOYU LIU]

I think the DC saturation performance can be done in the steady-state mode of charge. For AC, RF saturation output power can be done in the interconnection? For test the bandwidth in the ssac and transient, it seems contain  the internal RC effects, what is the value of internal R and C? Are they determined by the structure? If I only want to test the transit time bandwidth, how to do it?

[Khashayar Ghaffari]

Hi,

As you mentioned, SSAC and transient modes both account for the internal RC effects. The values depend on the design; the reported bandwidth is including for both RC and transit time. So if you are interested in sepearating each (e.g. in the format of tau(RC),tau(transit)) you would have to rely on the analytical models, and values used/reported in simulation. For example for transit time, the mean length and carrier velocities will be needed in your assesment.

Best

[HAOYU LIU]

For transient to test the bandwidth, the recombination parameters will not affect too much. But when using the ssac to test the bandwidth, the recombinations count a lot. For some situation, the bandwidth will decrease as the bias voltage increase and the UTC-PD bandwidth will decrease when using the graded doping in the absorption layer, it violate the principle. I want to know how to set the appropriate parameters in the ssac, the parameters in the example of vertical PD are not suitable for my model.