Two-color infrared focal plane detector and its mesa etching process method

Abstract

The present invention provides a two-color infrared focal plane detector and its mesa etching process method. The mesa etching process method includes steps: S1, spin-coating photoresist on the epitaxial structure; S2, using a half-tone mask The stencil exposes the epitaxial structure, and the first region and the second region are formed after the exposure of the epitaxial structure; S3, the first dry etching is performed by etching gas; S4, the first dry etching is performed by O 2 Plasma removes all parts of the photoresist below the second region; S5, performs second dry etching with etching gas; S6, removes the photoresist through a stripping process. In this application, the half-tone mask realizes the full exposure of the part requiring deep etching and the half exposure of the part requiring shallow etching on the epitaxial structure. Moreover, in the whole etching process, different depths of different parts can be etched through only one photolithography process and two dry etching processes, thereby simplifying the etching process flow and thus improving production efficiency.

Description

technical field [0001] The invention relates to the technical field of focal plane detectors, in particular to a two-color infrared focal plane detector and a mesa etching process method thereof. Background technique [0002] Two-color infrared focal plane detectors are mainly used in high-contrast imaging and target recognition. The two-color infrared detector system is compact in structure and light in weight, and can simultaneously detect two bands, which is one of the main development directions of the infrared detection system. Among them, the InAs / GaSb type II superlattice material is an ideal material for two-color infrared detection due to its special energy band structure, good material stability and multiple broad-spectrum response bands. The epitaxial structure of the second type of superlattice two-color infrared focal plane detector is usually NP-PN or PN-NP back-to-back stacked structure, and the middle is connected by a P-type or N-type common electrode. Man...

AI Technical Summary

Problems solved by technology

[0003] In the mesa etching process of the stacked material structure of the two-color infrared focal plane detector, the lower electrode needs to be etched deeply, and the common electrode needs to be etched shallowly. The traditional process flow is the part that needs deep etching and the part that needs shallow etching. The photolithography mask process is carried out separately and then etched separately, the process flow is cumbersome and the production efficiency is low

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