Rapid photo detector

Abstract

The invention relates to a rapid photo detector, belonging to the electronic component technology. The rapid photo detector comprises a photodiode and an amplification circuit connected with the photodiode, wherein the photodiode comprises an N+ substrate 101, an N- epitaxial layer 102, anode metal electrodes 105 and a cathode metal electrode 106, the N- epitaxial layer 102 is arranged at the upper end surface of the N+ substrate 101, a P+ injection area 103 is arranged in the N- epitaxial layer 102, and an anti-reflection coating 104 and the anode metal electrodes 105 are arranged at the upper end surface of the P+ injection area; and the amplification circuit is composed of multiple NMOS tubes 108 and PMOS tubes 109. The rapid photo detector is characterized in that a light shield layer is arranged between the photodiode and the amplification circuit, and the light shield layer is used for shielding light for non photosensitive areas. The rapid photo detector has the advantages that the generation condition for slow photo-generated carriers is fundamentally eliminated, and the response speed of the photo detector is greatly increased.

Description

Technical field [0001] The present invention relates to electronic component technology, in particular to a fast photodetector. Background technique [0002] Photo Detector (Photo Detector) is a kind of photodetector made of the photoelectric effect of semiconductor materials. When the photodetector receives light, the energy-carrying photons enter the PN junction of the photodiode, transfer the energy to the bound electrons on the covalent bond, and make some of the electrons break away from the covalent bond, thereby generating electron-hole pairs, called Photo-generated carriers, they participate in drifting motion under the action of reverse voltage, thereby generating reverse current, called photocurrent. If a load is connected to an external circuit, an electrical signal is obtained on the load, thus realizing the transition from optical signal to Conversion of electrical signals. These carriers are generated at different positions. In the area far from the electric field...

AI Technical Summary

Problems solved by technology

This structure has a better effect in solving the problem of vertical photogenerated carriers, but since photogenerated carriers also exist on the side of the N+ injection, these carriers cannot flow away quickly due to the distance from the electrode, which will affect the overall performance. responding speed

[0005] In summary, the method of improving the response speed of the photodetector by modifying the structure of the photodetector is complicated in structural design and cannot fundamentally eliminate the conditions for the generation of slow carriers.

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