Design And Performance Research Of Photodiodes Based On Magnesium Silicide Thin Film Materials

Magnesium silicide is a new semiconductor material with good optical absorption,which is a good near-infrared photoelectric material.In this paper,the design and performance of photomagnetization diodes for magnesium silicide were studied using a new material such as Mg₂Si.Combined with the process and material performance parameters of Mg₂Si,a set of physical models for the calculation of Mg₂Si photodiodes was proposed.This model and Silvaco TCAD can be used to simulate the forward voltage drop,maximum rectification current,reverse breakdown voltage,dark current and other electrical performance parameters as well as optical parameters such as sensitivity,quantum efficiency,detection rate,equivalent noise power and response time of Mg₂Si photodiodes.As to Mg₂Si homojunction PN photodiodes,the performance parameters of the homojunction PN photodiode were investigated by changing the thickness of the P-type doped layer,the doping concentration of the P-type doping layer,and the gradient of the doping concentration of the P and N-doped layer.The maximum responsivity of the homojunction PN photodiode can reach 0.413?A/W?,and the corresponding light wavelength is 875 nm.As to Mg₂Si homojunction PIN photodiodes,the performance parameters of the homojunction PIN photodiode were investigated by changing the thickness of the P-type doping layer,the thickness of the I-type doping layer,the thickness of the N-type doping layer,and the doping concentration of the I-type doping layer.The maximum responsivity of the homojunction PIN photodiode can reach 0.433?A/W?,and the maximum responsivity is corresponding to the light wavelength of 965 nm.The detectivity of the PIN structure can reach 1.44×10¹¹ cm?Hz^1/2W^-1,and the corresponding light wavelength is 940 nm.Theoretical calculations show that Mg₂Si is of good photoelectric conversion properties and high resolution characteristics in the near-infrared.The Mg₂Si film is of good absorption in the range of 800-1000 nm in the infrared,and can be used to fabricate near-infrared photodiodes.