Silicon-based modulator and modulation device

Abstract

The embodiment of the invention discloses a silicon-based modulator and a modulation device. The modulator comprises a waveguide, and the waveguide comprises a positive doped region, a negative dopedregion, a heavy positive doped region, a heavy negative doped region, a cathode, and an anode, wherein the positive doped region is connected with the cathode through the heavy positive doped region,the negative doped region is connected with the anode through the heavy negative doped region, the positive doped region and the negative doped region form a positive-negative junction arranged in themiddle of the waveguide, the heavy positive doped region and the heavy negative doped region are arranged at the two ends of the waveguide, the cross section of an interface between the positive doped region and the negative doped region is a broken line, the broken line comprises n line segments, and n is greater than or equal to 3. According to the embodiment of the invention, the boundary between the positive doped region and the negative doped region is Z-shaped, so that the overlapping region area of the depletion region of the positive-negative junction formed by the positive doped region and the negative doped region and the light field is larger, the modulation efficiency is improved, the depletion region of the positive-negative junction does not need to be heavily doped, and theoptical loss is reduced.

Description

technical field [0001] Embodiments of the present invention relate to but are not limited to the field of optical communication, especially a silicon-based modulator and modulation device. Background technique [0002] With the development of computer and communication technology, the demand for information in modern society is increasing exponentially. As a strong competitor of communication link system based on copper materials, optical communication technology develops rapidly. [0003] A key device in the optical communication system is a high-speed modulator, which usually uses an external electric field to change the physical properties of the material, so that the output of the device exhibits characteristics that vary with the external electric field, and realizes data signals on the optical carrier. load. A typical modulator uses the linear electro-optic effect of lithium niobate material to modulate the optical carrier; materials such as indium phosphide and gall...

AI Technical Summary

Problems solved by technology

[0005] The main problem of the current silicon-based high-speed carrier dispersion modulator is that the modulation efficiency is not high. For the modulator with a limited modulation region length, a high driving voltage is required to achieve the ideal modulation depth, which brings power consumption problem

Although the modulation efficiency can be improved to a certain extent by increasing the doping concentration, the optical loss caused by carrier absorption will increase sharply.

In addition, the modulation efficiency can also be improved by designing an "L-shaped" PN junction (that is, the shape of the PN junction depletion region is similar to the English letter "L"), although the overlapping area between the PN junction depletion region and the optical field is limited. A certain increase, but the modulation efficiency is still relatively low. In order to achieve higher modulation efficiency, relatively heavy doping is still required, which will inevitably bring higher optical loss

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