LDMOS-Integrated Silicon Photonic Modulators
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current silicon photonic devices face challenges in integrating high voltage and low power modulators effectively, as existing technologies struggle to balance power consumption and modulator performance.
Innovation Solution
Integration of laterally diffused metal-oxide-semiconductor (LDMOS) devices with silicon photonic devices, where LDMOS transistors are used to provide a phase shift in optical modulators, allowing for low power consumption while supporting high operating voltages by adjusting the refractive index of silicon waveguides through bias voltage control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If forward-biased diodes are used to inject large current for low voltage operation, then large index shift is achieved, but power consumption increases
Solution Approach 1:
The patent changes the operating parameters by using LDMOS transistors instead of forward-biased diodes, operating at high voltage (e.g., 50V) with controlled current to achieve the desired index shift while reducing power consumption. The LDMOS device allows operation in the saturation region where high voltage and low current coexist
Solution Approach 2:
The patent substitutes the diode-based electrical injection mechanism with an LDMOS transistor-based electric field control mechanism. The LDMOS transistor uses gate voltage control to modulate the channel conductivity, replacing the direct current injection approach with a more efficient field-effect control approach
2Power
If LDMOS devices are integrated with silicon photonic devices, then high voltage capability is achieved, but device complexity increases
Solution Approach 1:
The patent merges the LDMOS transistor fabrication process with the silicon photonic device fabrication process into a single integrated manufacturing flow. Both device types are formed on the same silicon substrate using compatible CMOS processing steps, including shared photolithography, etching, and deposition processes
Solution Approach 2:
The patent creates a universal fabrication platform that can produce both LDMOS high-voltage devices and silicon photonic waveguide devices using the same process toolkit. The process is designed to accommodate different device structures (transistors, waveguides, modulators) through a single set of manufacturing steps
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables the development of low power optical modulators with high voltage capabilities, enhancing the efficiency and performance of silicon photonic devices by selectively applying phase shifts to light signals.
Implementation Method 1
allowing for low power consumption while supporting high operating voltages by adjusting the refractive index of silicon waveguides through bias voltage control
Data Source
AI summary
A device includes a laterally diffused metal-oxide-semiconductor (LDMOS) device integrated with an optical modulator. An optical waveguide of the optical modulator includes a silicon-containing structure in a drift region of the LDMOS device.