Optical Integrated Circuits Using Single Crystalline Silicon Cores

Solution Overview

Problem

The high production cost of optical integrated circuits on silicon-on-insulator substrates and the associated high light loss when manufacturing on bulk substrates using amorphous silicon, which limits the efficiency of optical devices.

Innovation Solution

The use of a substrate with a single crystalline semiconductor material, including an active device with a first core made of single crystalline silicon and a passive device with a second core made of silicon nitride, which has a lower refractive index than the first core, to reduce light loss and improve the characteristics of optical integrated circuits.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If optical integrated circuits are formed on a silicon-on-insulator (SOI) substrate, then the production cost increases, but the light loss is reduced

Engineering Contradiction:

Improvelight lossVSAvoidproduction cost

Core Design Contradiction:

Loss of energyVSEase of manufacture

Solution Approach 1:

The patent applies local quality by using single crystalline silicon only in the core region where light propagation occurs, while the surrounding cladding and substrate use amorphous silicon or other materials. This localized application of high-quality material minimizes light loss in the critical path while avoiding the high cost of using single crystalline silicon throughout the entire device structure.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs composite materials by combining single crystalline silicon cores with amorphous silicon cladding layers and insulation regions. This composite structure leverages the low light loss property of single crystalline silicon in the core while using cost-effective amorphous silicon for the surrounding structures, thus reducing overall production cost while maintaining optical performance.

Inventive Principle:

Principle #40Composite materials

2Ease of manufacture

If amorphous silicon is deposited and regrown to form optical devices on a bulk substrate, then the production cost decreases, but the light loss increases

Engineering Contradiction:

Improveproduction costVSAvoidlight loss

Core Design Contradiction:

Ease of manufactureVSLoss of energy

Solution Approach 1:

The patent applies local quality by using single crystalline silicon only in the core region where light propagation occurs, while the surrounding cladding and substrate use amorphous silicon or other materials. This localized application of high-quality material minimizes light loss in the critical path while avoiding the high cost of using single crystalline silicon throughout the entire device structure.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs composite materials by combining single crystalline silicon cores with amorphous silicon cladding layers and insulation regions. This composite structure leverages the low light loss property of single crystalline silicon in the core while using cost-effective amorphous silicon for the surrounding structures, thus reducing overall production cost while maintaining optical performance.

Inventive Principle:

Principle #40Composite materials

3Speed

If a single crystalline semiconductor substrate is used, then the data transfer speed is improved, but the device complexity increases

Engineering Contradiction:

Improvedata transfer speedVSAvoiddevice complexity

Core Design Contradiction:

SpeedVSDevice complexity

Solution Approach 1:

The patent applies segmentation by dividing the optical device into distinct functional regions: single crystalline silicon cores for active light propagation and amorphous silicon regions for passive cladding and insulation. This segmentation allows high-speed data transfer in the core while simplifying the overall device structure by using standard semiconductor fabrication processes for the surrounding materials.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies universality by using amorphous silicon to serve multiple functions simultaneously: as cladding material for optical confinement, as insulation layer between devices, and as substrate material. This multi-functionality reduces device complexity by eliminating the need for separate SOI substrate structures while maintaining high-speed performance in the single crystalline core regions.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 enhances the performance of optical integrated circuits by reducing light loss and improving data transfer efficiency while maintaining high-speed capabilities, thus addressing the limitations of existing technologies.

Implementation Method 1

The second core may include a material including a refractive index that is lower than that of the first core

Methodology Applied

Scientific EffectRefraction: Refraction

Data Source

PatentUS10901151B2Optical integrated circuits

Publication Date: 2021.01.26 SAMSUNG ELECTRONICS CO LTD

AI summary

Optical integrated circuits are provided. An optical integrated circuit includes a substrate including a single crystalline semiconductor material. The optical integrated circuit includes an insulation region in a trench in the substrate. The optical integrated circuit includes a first core on the insulation region. The first core includes the single crystalline semiconductor material. Moreover, the optical integrated circuit includes a second core that is spaced apart from the first core. The second core includes a material having a refractive index that is lower than that of the first core.