Preparation method of micro-bridge structured infrared detector, and micro-bridge structure

Abstract

The invention relates to a preparation method of a micro-bridge structured infrared detector, and a micro-bridge structure. The method comprises the steps that: a metal reflective layer and a sacrificial layer are sequentially deposited on an infrared detector readout circuit substrate; PI holes are etched on the sacrificial layer, wherein the PI holes are positioned at an out-leading electrode of the readout circuit; a deposition support layer, a thermo-sensitive layer and a protective layer are sequentially deposited on the sacrificial layer; through holes are prepared in the PI holes, and a contact hole is prepared on the protective layer; electrode layer metal is deposited on the protective layer, and U-shaped metals with bridge pier structures are filled in the PI holes and the through holes; and U-shaped metal structures are formed through photolithography and etching; photolithography and etching is carried out upon the electrode layer metal; a passivation layer is deposited on the surface of the device, and the passivation layer is subjected to photolithography and etching, such that a passivation layer pattern is formed; and sacrificial layer releasing is carried out, such that the micro-bridge structure is formed. According to the invention, a U-shape filling method is adopted, and Al is adopted as a filling material. Therefore, sputtering and depositing are easy, and etching is convenient. The heat insulation property of the detector is better than that of a copper filling process, and a CMP step is not needed.

Description

technical field [0001] The invention belongs to the field of micro-electro-mechanical systems (MEMS, Micro-Electro-Mechanical Systems) manufacturing in semiconductor technology, and specifically relates to a manufacturing method of an uncooled infrared focal plane array detector, in particular to a pier structure of a micro-bridge. A new preparation method and microbridge structure. Background technique [0002] Uncooled infrared detection technology is a technology that senses the infrared radiation (IR) of external objects without a cooling system and converts it into an electrical signal that is processed and output on the display terminal. It can be widely used in many fields such as national defense, aerospace, medicine, production monitoring, etc. . Uncooled infrared focal plane detectors are able to work at room temperature, and have the advantages of light weight, small size, long life, low cost, low power, fast startup and good stability, etc., which meet the needs...

AI Technical Summary

Problems solved by technology

This method uses Cu and W metal pillars, and the thermal insulation of the pier is poor, which affects the sensitivity and response rate of the detector, and introduces a CMP planarization process, which greatly increases the production cost

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