Semiconductor Passivation Layer for Germanium Leakage Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Germanium-based photonic devices suffer from higher leakage currents and dark current susceptibility due to their smaller band gap and interfacial defects, which hinder their performance compared to silicon-based devices.
Innovation Solution
An integrated chip structure is developed with a second semiconductor material like germanium on a silicon substrate, where a passivation layer is used to cover the germanium, reducing interfacial defects and leakage currents by passivating the upper surface, thereby enhancing the performance of photonic devices such as depth sensors and image sensors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If germanium-based photonic devices are used, then near-infrared absorption and quantum efficiency are improved, but leakage currents and dark current susceptibility increase
Solution Approach 1:
A silicon-based passivation layer is introduced as an intermediary between the germanium photonic device and the external environment. This passivation layer mediates the interaction by providing defect passivation that reduces leakage currents and dark current susceptibility, while allowing the germanium device to maintain its superior near-infrared absorption and quantum efficiency properties
Solution Approach 2:
The electrical properties of the germanium device surface are changed through the application of a passivation layer. This layer modifies the surface parameters by reducing interface defects and trap states, thereby changing the electrical behavior from high leakage current to low leakage current operation while preserving the optical absorption characteristics
2Use of energy by moving object
If germanium-based photonic devices are used, then near-infrared absorption is improved, but interfacial defects increase
Solution Approach 1:
The silicon passivation layer serves as an intermediary that interfaces with the germanium photonic device. It provides a stable interface that passivates defects, thereby improving reliability without compromising the near-infrared absorption capability of the germanium material
Solution Approach 2:
A composite structure is formed by combining silicon passivation layer with germanium photonic device. This composite material system leverages the complementary properties of both materials: silicon provides defect passivation and stability, while germanium provides superior near-infrared absorption, achieving both high reliability and high performance
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
The passivation layer effectively reduces leakage currents and improves the performance of photonic devices by minimizing defects, leading to better absorption and quantum efficiency in near-infrared applications.
Implementation Method 1
The passivation layer is configured to passivate defects disposed along an upper surface of the second semiconductor material
Data Source
AI summary
The present disclosure relates to an integrated chip. The integrated chip includes a substrate having a first semiconductor material. A second semiconductor material is disposed on the first semiconductor material. The second semiconductor material is a group IV semiconductor or a group III-V compound semiconductor. A passivation layer is disposed on the second semiconductor material. The passivation layer includes the first semiconductor material. A first doped region and a second doped region extend through the passivation layer and into the second semiconductor material.