Photoelectric diode structure and manufacturing method thereof

Abstract

The invention discloses a photoelectric diode structure and a manufacturing method thereof. The method comprises the following steps of: providing a substrate on which a front side and a back side are defined; sequentially forming an epitaxial layer and a first conducting layer on the front side of the substrate; etching the back side of the substrate to penetrate the epitaxial layer so as to form a groove, wherein the groove is defined with a side wall and exposes the first conducting layer; forming an insulating layer to cover the side wall, wherein the insulating layer is defined with an opening and exposes the first conducting layer; and forming a second conducting layer on the back side of the substrate, wherein the second conducting layer comprises mutually isolated first and secondelectrodes and the first electrode covers the insulating layer and fills the opening so as to be connected with the first conducting layer. According to the structure and the method of the invention,a contact electrode on the side facing to the light is moved to the backlight side through a buried hole so as to reduce the area occupied by the conducting layer of the side facing to light and increase the exposable area of the side facing to light.

Description

technical field [0001] The present invention relates to a photodiode structure and a manufacturing method thereof, more particularly to a flip-chip photodiode structure and a manufacturing method thereof. Background technique [0002] The principle of photodiodes is based on the photovoltaic effect of semiconductors to convert light energy into electrical energy. A photodiode consists of a P-N junction of semiconductors of different electrical properties. Under light irradiation, the light is absorbed by the P-N junction to generate electric current. Generally speaking, the N-type electrode of the photodiode structure is disposed on the light-facing side of the photodiode structure, and the P-type electrode is disposed on the backlight side of the photodiode structure, and its external connection is usually through bonding. [0003] Figure 1A A top view illustrating a known photodiode element 100, Figure 1B Example along Figure 1A The cross-sectional view of the I-I' l...

AI Technical Summary

Problems solved by technology

In order to facilitate the wire bonding process, the second portion 120b needs to have a sufficiently wide area, which will reduce the light-receiving area of ​​the photodiode element 100, thereby reducing the performance of the photodiode structure 100.

Moreover, the wire bonding structure 140 will also cause the inconvenience of connecting the photodiode elements 100 in series and in parallel.

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