Bottle-Shaped Isolation Structure for Leakage Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional integrated circuit structures suffer from current leakage through the wide portions of the semiconductor substrate and the 'floating body effect' in silicon-on-insulator substrates, which are costly and have low throughput.
Innovation Solution
The integration of a bottle-shaped shallow trench isolation structure with a mushroom-shaped pillar, featuring a dielectric layer and an insulating region, reduces substrate leakage and inherently provides a current path, eliminating the need for additional paths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a conventional planar transistor structure with standard shallow trench isolation is used, then the fabrication process is simple and cost-effective, but current leakage occurs through the wide portion of the semiconductor substrate below the gate and diffusion regions
Solution Approach 1:
The isolation structure is divided into two distinct segments: a first isolation structure filling the trench and a second isolation structure formed over the first isolation structure. This segmentation allows the first isolation structure to provide electrical isolation while the second isolation structure provides mechanical support and prevents substrate leakage, thereby resolving the contradiction between fabrication simplicity and current leakage prevention.
Solution Approach 2:
The invention transitions from a conventional single-layer isolation structure to a multi-layer isolation structure with vertical dimensionality. By adding the second isolation structure formed over the first isolation structure, the solution addresses current leakage through the substrate by providing an additional isolation layer that blocks leakage paths, while maintaining compatibility with standard fabrication processes.
2Ease of manufacture
If conventional single-layer shallow trench isolation is used, then the process is straightforward and cost-effective, but thermal conductivity is insufficient and parasitic capacitance is not optimized
Solution Approach 1:
The invention employs a composite isolation structure consisting of two different isolation structures with potentially different material compositions. The first isolation structure filling the trench and the second isolation structure formed over it create a composite system that optimizes both thermal conductivity and electrical isolation properties, resolving the contradiction between process simplicity and thermal 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
This configuration effectively addresses current leakage and the floating body effect, enhancing thermal conductivity and reducing parasitic capacitance without the need for extra current paths or expensive processes.
Implementation Method 1
an isolation structure positioned in the insulating region and including a bottle portion and a neck portion filled with a dielectric material
Implementation Method 2
the portion of the semiconductor substrate directly below the device region is much narrower, which can effectively solve the current leakage problem
Data Source
AI summary
An integrated circuit structure comprises a semiconductor substrate, a device region positioned in the semiconductor substrate, an insulating region adjacent to the device region, an isolation structure positioned in the insulating region and including a bottle portion and a neck portion filled with a dielectric material, and a dielectric layer sandwiched between the device region and the insulation region.