Measurement of Ge Electrical Parameters by Analysing its Optical Dynamics

Abstract

By using a dynamical model giving both the IR reflectivity and transmittivity of a semiconductor after an intense photo-plasma production, it is possible to derive several electrical parameters, as Auger recombination, radiative recombination and impurity recombination. The model has been tested on previous experimental works and used to analyse the 10.6 µm dynamical transmission reflection induced by a 1.06 ns excitation in Ge optical windows.

Toward a Germanium Laser for Integrated Silicon Photonics

“…In the calculations before, we have used a conservative direct band-to-band radiative recombination lifetime of 10 ns derived from the measured direct radiative recombination constant in [10]. The Auger coefficient used in this calculation is 10 −30 cm −6 /s, one order of magnitude higher than reported values for both p-n-n and n-n-p processes [24], [25]. Therefore, the 10% efficiency shown here is the lower limit of Ge direct-gap light emission, and it is promising for the EL efficiency of tensile-strained n + Ge to reach similar efficiencies as direct-gap III-V materials on Si.…”

Band-engineered Ge-on-Si lasers

“…With a proper heterojunction design, e.g., p-Si doped at 5×10 19 cm -3 and n-Si doped at 1×10 19 cm -3 , internal quantum efficiencies as high as 10% can be achieved, which is very promising for an indirect bandgap material. In the calculations above, we have used a conservative Auger coefficient of 10 -30 cm -6 /s, one order of magnitude higher than reported values for both pnn and nnp processes (11,12). Therefore, the 10% efficiency shown here is the lower limit of Ge direct gap light emission, and it is promising for the EL efficiency of tensile-strained n + Ge to reach similar efficiencies as direct gap III-V materials on Si.…”

Monolithic Ge-on-Si lasers for integrated photonics

“…With a proper heterojunction design, e.g., p-Si doped at 5×10 19 cm -3 and n-Si doped at 1×10 19 cm -3 , internal quantum efficiencies as high as 10% can be achieved, which is very promising for an indirect bandgap material. In the calculations above, we have used a conservative Auger coefficient of 10 -30 cm -6 /s, one order of magnitude higher than reported values for both pnn and nnp processes in Ge [18,19]. Therefore, the 10% efficiency shown here is the lower limit of Ge direct gap light emission, and it is promising for the EL efficiency of tensilestrained n + Ge to reach similar levels as direct gap III-V materials on Si.…”