Infrared focal plane detector and manufacturing method thereof

Abstract

The invention discloses a manufacturing method of an infrared focal plane detector. The method comprises the following steps: arranging a passivation layer on the upper surface of a p-type substrate; performing whole-surface injection on the p-type substrate through the passivation layer to obtain a continuous n-type doped layer; photoetching an isolation groove pattern on the surface of the passivation layer, and etching according to the isolation groove pattern to obtain a patterned isolation groove which penetrates through the passivation layer and the n-type doping layer and of which the bottom surface is in contact with the p-type substrate, so as to prepare the infrared focal plane detector, wherein the n-type doped layer comprises a plurality of detection pixels which are separated by the isolation grooves. The adjacent detection pixels are spatially separated through the isolation grooves, the crosstalk phenomenon between the detection pixels is avoided, the detection precision of the detector is improved, the signal strength is guaranteed, ion implantation doping does not need to be carried out through a photoresist layer, and the problem of surface pollution residues before implantation is avoided. The invention also provides an infrared focal plane detector with the above beneficial effects.

Description

technical field [0001] The invention relates to the field of infrared detection, in particular to an infrared focal plane detector and a manufacturing method thereof. Background technique [0002] With the development of technology, infrared detectors are widely used in military and civil fields such as early warning detection, infrared reconnaissance, and imaging guidance. The preparation of infrared detector chips is the core of infrared detection technology. With the continuous development of infrared detector technology, the spacing of photosensitive elements of focal plane arrays is getting smaller and smaller, and the resolution and sensitivity are constantly improving. At the same time, along with the diffraction effect related to the detection target wavelength, the crosstalk phenomenon between pixels is also more obvious. A typical HgCdTe infrared detector manufacturing process usually uses a high-precision photolithography process combined with a planar implantati...

AI Technical Summary

Problems solved by technology

[0003] In the preparation process of the existing mercury cadmium telluride infrared focal plane detector, after the injection junction process is completed, the size of the implanted area will have a certain lateral diffusion, and improper control will cause electrical connection between photosensitive elements (ie, detection pixels), resulting in The crosstalk between photosensitive elements is serious; in order to avoid crosstalk, the method of reducing the injection area is generally designed. In this case, it is easy to cause signal attenuation and cause the performance of the infrared detector to decline. Please refer to figure 1 , figure 1 It is a schematic diagram of the structure of the diffusion of the mercury cadmium telluride infrared detector when it is implanted.

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