Method for preparing hybrid integrated fiber optic gyroscope optical chip

Abstract

The invention belongs to the technical field of semiconductor processes, and in particular to a method for preparing a hybrid integrated fiber optic gyroscope optical chip. The chip comprises a substrate, a light source, a silicon-based 3dB coupler, a lithium niobate Y branch phase modulator and a signal detector, the silicon-based 3dB coupler is based on the silicon-based silicon dioxide opticalwaveguide technology and comprises a Y branch waveguide, two 90-degree circular arc waveguides, a tapered waveguide and two straight waveguides, which communicate with each other, a wide end of the tapered waveguide is used as an optical input port of the optical chip, the light source is aligned to the optical input port, the straight waveguide connected with a Y branch is used as a signal outputport of the optical chip, a photosensitive surface of the signal detector is aligned to the signal output port, and the straight waveguide connected with the 90-degree circular arc waveguide is usedas an optical transmission port and is spiced and fixed with a base waveguide end face of the lithium niobate Y branch phase modulator 3 through a waveguide coupling process. By adoption of the methodprovided by the invention, an optical fiber fusion point is removed, and the method has the advantages of high integration degree, small volume, low power consumption, good performance, good reliability and environmental adaptability, etc.

Description

technical field [0001] The invention belongs to the technical field of semiconductor technology, and in particular relates to a preparation method of a hybrid integrated fiber optic gyro optical chip. Background technique [0002] In many military and civilian applications such as aircraft and ship navigation, missile guidance, satellite orientation, geodesy, astronomical telescope observation and tracking, automotive GPS system-assisted navigation, and automotive autopilot, it is necessary to use small, high-reliability, and cheap inertial measurement devices. . Fiber optic gyroscope is an all-solid-state inertial instrument that uses the Sagnac effect to be sensitive to rotation or angular rate of rotation. It has light weight, low power consumption, low cost, long life, insensitive to acceleration, small size, no moving parts and good bias stability. It has better application prospects than laser gyro or other electromechanical gyroscopes due to its advantages such as sm...

AI Technical Summary

Problems solved by technology

[0003] However, the existing fiber optic gyro system has certain technical defects: it is composed of some discrete components, each packaged, and the system is bulky; there are many optical fiber fusion points, which are prone to failure, and the system environment adaptability and reliability are poor; the cost is high, which is not conducive to engineering. Advanced production: each discrete component must be coupled with the device pigtail, with many and complex procedures, low coupling efficiency, and difficult to guarantee system repeatability

[0004] At present, the advanced interferometric fiber optic gyroscope optical system mainly includes superluminescent light-emitting diodes, fiber couplers, lithium niobate multifunctional integrated optical Y waveguide modulators, fiber optic rings, and photodetectors, which mainly rely on lithium niobate multifunctional integrated optical modulation. The chip is used to realize the phase modulation and optical beam splitter functions required by the inertial measurement system. However, due to the large bending loss of the lithium niobate waveguide, the inclination angle is usually between 3° and 5°, the size is large, and the manufacturing process is different from that of the optical beam splitter. The compatibility of semiconductor technology and its integration with semiconductor photonic devices are also poor, and the cost is also high, which limits the further integration and miniaturization of fiber optic gyroscopes

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