High Efficiency Bandwidth Product Germanium Photodetector

Abstract

The invention discloses a high efficiency bandwidth product Ge light detector; a groove with an opening facing downward is etched on a silicon substrate; a metal reflection mirror surface layer is plated on an inner periphery of the groove; a dielectric reflection mirror surface layer is added on the light detector; a Ge light adsorption layer is clamped between the metal reflection mirror surface layer and the dielectric reflection mirror surface layer, so a P-I-N structure or other type structures can be formed; the structure is matched with critical coupling formula regulation of a resonant cavity, so all incident light can be completely locked in the cavity structure between the metal reflection mirror surface layer and the dielectric reflection mirror surface layer so as to reach critical coupling; 100% adsorption efficiency can be approximately reached without light leakage; choices between the bandwidth and efficiency can be breached on a base of critical coupling, so high response level and high bandwidth more than 50GHz can be obtained, thereby enhancing light-to-electricity adsorption efficiency.

Description

technical field [0001] The present invention relates to a photodetector, in particular to a high-efficiency bandwidth product germanium photodetector, in particular to a cavity structure in which all incident light can be completely blocked by upper and lower reflectors to achieve critical coupling, It can have nearly 100% absorption efficiency without light leakage, and then break through the trade-off between bandwidth and efficiency on the basis of critical coupling to achieve high responsivity and high bandwidth, so as to increase the efficiency of light-to-electricity absorption. Background technique [0002] At present, photodetector technology has been matured and applied to various optical communication products. In the semiconductor photodetector, when the photodetector is exposed to the light source, the photodetector absorbs the light energy through the sensing body and converts it into an electronic signal to output a current, which can be used for optical commun...

AI Technical Summary

Problems solved by technology

therefore Figure 4 The photodetector shown cannot achieve high efficiency bandwidth product

Moreover, this technology cannot make the reflective surface under the substrate 300 into a planar structure, and the design is obviously limited. The slope below the substrate 300 also needs to be at a certain angle to reflect effectively. If the angle is not calculated properly, or there is a slight deviation during the manufacturing process , it will lead to a path difference during light reflection, which will affect the light absorption efficiency

Therefore, generally used products cannot meet the needs of users to achieve no light leakage in actual use.

Images