Adjustable optical attenuator and making method thereof

Abstract

The invention relates to an adjustable optical attenuator and a making method thereof, and belongs to the field of optical communication. The adjustable optical attenuator comprises a silicon dioxide substrate and an external silicon dioxide upper coating arranged on the silicon dioxide substrate; a groove is formed in the external silicon dioxide upper coating, a side trench is formed between the external silicon dioxide upper coating and the groove, and a thermo-luminescent material is filled in the side trench; a sealing cap is covered on the external silicon dioxide upper coating, the side trench and the groove; a waveguide core is arranged at the bottom of the groove, and the upper part of the waveguide core is provided with an internal silicon dioxide upper coating; and a metal electrode is arranged at the joint of the inner part of the sealing cap and the internal silicon dioxide upper coating. By directly growing the waveguide core on the silicon dioxide substrate, the growth time of a silicon dioxide lower coating is reduced, the growth period of a product is shortened, and the cost of the product is reduced; and in addition, because the substrate and the lower coating are made of the same material, the stress influence of the substrate on the device is eliminated, and the polarization related loss of the device is effectively reduced.

Description

technical field [0001] The invention relates to an adjustable optical attenuator and a manufacturing method thereof, belonging to the field of optical communication. Background technique [0002] Variable optical attenuator (VOA) has a wide range of applications in optical communication transmission systems, and its main function is to attenuate or control optical signals. The most basic characteristic of optical communication transmission system should be adjustable, especially with the application of DWDM (Dense Wavelength Division Multiplexing) transmission system and EDFA (Erbium-doped Fiber Amplifier) ​​in optical communication, in multiple optical signal transmission channels Gain flattening or channel power equalization must be performed on the optical receiver, and dynamic saturation control must be performed at the optical receiver. In addition, other signals need to be controlled during optical transmission. These make the VOA array an indispensable key device. ...

AI Technical Summary

Problems solved by technology

[0006] The Silica-on-silicon technology platform is to grow the lower cladding layer and waveguide core of silicon dioxide on the silicon wafer. Although the mature ion-enhanced chemical vapor deposition process (PECVD) in the semiconductor industry is used, the silicon Growing silicon dioxide on a circle not only takes a long time, but also costs a lot. In addition, due to the two different materials, the stress of the formed device is relatively large, and the polarization-dependent loss (PDL) of the device is also large.

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