Variable-Width Optical Waveguide for Lower Modulation Loss

Solution Overview

Problem

Current semiconductor devices experience significant signal loss when propagating optical signals due to the narrow width of waveguide portions between p-type and n-type semiconductor structures, leading to inefficiencies in optical communication and modulation.

Innovation Solution

The semiconductor device incorporates a waveguide with a second portion having a wider width than the first portion, positioned between doped semiconductor structures, along with tapered sidewalls to control optical signal propagation and reduce signal loss, utilizing a configuration that includes n-doped and p-doped semiconductor structures for modulation and phase shifting.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the waveguide width between doped semiconductor structures is narrow, then the device size is reduced, but signal loss increases

Engineering Contradiction:

Improvedevice sizeVSAvoidsignal loss

Core Design Contradiction:

Volume of moving objectVSLoss of energy

Solution Approach 1:

The waveguide is divided into multiple portions with different widths: a first portion with a first width, a second portion with a second width larger than the first width, and a third portion with a third width. This segmentation allows the waveguide to optimize signal propagation in the middle section while maintaining compact dimensions at the ends, thereby reducing overall signal loss without significantly increasing device size.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the waveguide are assigned different width characteristics tailored to their specific functions. The middle portion has a larger width to minimize signal loss during propagation, while the end portions have smaller widths to maintain compact device dimensions. This local differentiation of geometric properties optimizes both signal transmission and space utilization.

Inventive Principle:

Principle #3Local quality

2Loss of energy

If the waveguide width is increased to reduce signal loss, then signal propagation efficiency improves, but device area increases

Engineering Contradiction:

Improvesignal lossVSAvoiddevice area

Core Design Contradiction:

Loss of energyVSArea of stationary object

Solution Approach 1:

The waveguide is divided into multiple portions with different widths: a first portion with a first width, a second portion with a second width larger than the first width, and a third portion with a third width. This segmentation allows the waveguide to optimize signal propagation in the middle section while maintaining compact dimensions at the ends, thereby reducing overall signal loss without significantly increasing device size.

Inventive Principle:

Principle #1Segmentation

3Ease of manufacture

If uniform waveguide width is used, then manufacturing is simplified, but signal loss increases due to narrow dimensions

Engineering Contradiction:

Improvewaveguide fabricationVSAvoidsignal loss

Core Design Contradiction:

Ease of manufactureVSLoss of energy

Solution Approach 1:

The waveguide is divided into multiple portions with different widths: a first portion with a first width, a second portion with a second width larger than the first width, and a third portion with a third width. This segmentation allows the waveguide to optimize signal propagation in the middle section while maintaining compact dimensions at the ends, thereby reducing overall signal loss without significantly increasing device size.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The waveguide includes tapered portions where the width transitions gradually between the first, second, and third portions. These tapered sections with curved/gradual width changes reduce signal reflections and impedance mismatches, maintaining manufacturing feasibility while improving signal propagation efficiency compared to abrupt width changes.

Inventive Principle:

Principle #14Spheroidality (Curvature)

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 configuration significantly reduces signal loss, allowing for more efficient optical communication and modulation by optimizing the waveguide dimensions and doping structures, thereby enhancing the propagation of optical signals.

Implementation Method 1

The waveguide includes a first portion having a first width, a second portion having a second width larger than the first width, and a third portion having a third width. The second portion of the waveguide is between the first doped semiconductor structure and the second doped semiconductor structure.

Methodology Applied

Scientific EffectOptical waveguide propagation: Waveguide (optics)

Implementation Method 2

a first doped semiconductor structure and a second doped semiconductor structure. The second portion of the waveguide is between the first doped semiconductor structure and the second doped semiconductor structure

Methodology Applied

Scientific EffectElectro-optic modulation: Electro-Optic Effects

Data Source

PatentUS11869991B2Semiconductor device and method of making

Publication Date: 2024.01.09 TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

AI summary

A semiconductor device is provided. The semiconductor device includes a waveguide over a first dielectric layer. A first portion of the waveguide has a first width and a second portion of the waveguide has a second width larger than the first width. The semiconductor device includes a first doped semiconductor structure and a second doped semiconductor structure. The second portion of the waveguide is between the first doped semiconductor structure and the second doped semiconductor structure.