A novel InGaAs photodiode fabrication and its application

In this study, a two-dimension array of InGaAs photodiode with 0.9~1.7nm absorption wavelength was presented. By using the characteristic of wide wavelength range in InGaAs material, we designed several active regions in our novel devices for inducing expected photocurrent. While the distances between light source and these several equal-area active regions increases, we found the current generated in photodiode decreases non-linearly. Furthermore, this device was applied on detecting skin physiology, when the tungsten bulk light source penetrated through skin and was absorbed by photodiode, there had individual different currents in each equal-area active regions, and the relationship between photocurrent and moisture in skin will be interpreted.