SOI Semiconductor Vacuum Gap Contact Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor technologies do not fully meet the requirements for forming conductive and isolation structures on semiconductor on insulator (SOI) substrates, particularly in terms of efficient voltage application to the bottom substrate, leading to challenges in manufacturing processes and circuit design.
Innovation Solution
A semiconductor device and manufacturing method that include a buried oxide layer, a semiconductor layer, and a dielectric layer with specific trench structures and vacuum gaps, allowing for the formation of contact and isolation structures without additional etching masks, enabling direct definition of their positions and reducing manufacturing complexity and costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional methods are used to form conductive and isolation structures on SOI substrates, then additional etching masks and multiple processing steps are required, but this increases manufacturing complexity and costs
Solution Approach 1:
The patent combines the formation of isolation structures (vacuum gaps) and conductive structures into a single integrated process. The dielectric layer is deposited to seal the first trench while leaving the second trench open for conductive material filling, eliminating the need for separate masking and etching steps that would normally be required for each structure type.
Solution Approach 2:
The dielectric layer is deposited in advance to seal the first trench before the second trench is filled with conductive material. This preliminary sealing action defines the positions of both isolation and conductive structures simultaneously, preventing the need for subsequent masking operations and simplifying the overall manufacturing sequence.
2Reliability
If a thicker dielectric layer is used to ensure proper sealing and isolation, then isolation integrity is improved, but device dimensions and complexity increase
Solution Approach 1:
The dielectric layer is applied with different thicknesses at different locations: it is thick enough to seal the first trench and provide proper isolation, while being removed or not deposited in the second trench area where conductive material needs to reach the substrate. This localized variation in dielectric thickness ensures isolation integrity without unnecessarily increasing overall device complexity.
Solution Approach 2:
The dielectric layer is deposited to partially fill and seal the first trench, providing sufficient isolation without completely filling it. This partial action ensures proper sealing and electrical isolation while maintaining appropriate dimensions and avoiding excessive dielectric thickness that would complicate the device structure.
3Ease of manufacture
If vacuum gaps are formed by completely filling trenches with dielectric material, then manufacturing is simpler, but the vacuum gap structure and isolation performance are lost
Solution Approach 1:
The dielectric layer is deposited to partially fill the first trench, providing just enough material to seal the trench opening and maintain vacuum isolation, but not so much that it completely fills the trench and eliminates the vacuum gap. This controlled partial filling maintains both manufacturing simplicity and vacuum gap functionality.
Solution Approach 2:
The dielectric layer is selectively applied to seal the first trench while leaving the second trench open. The local variation in dielectric presence ensures that the vacuum gap structure is maintained in the first trench for isolation purposes, while the second trench remains accessible for conductive material filling.
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 method simplifies the manufacturing process, reduces material costs, and provides effective isolation and conductive structures, improving the flexibility of circuit layout and reducing the thickness of the dielectric layer, while maintaining good isolation and contact integrity.
Implementation Method 1
the first dielectric layer seals the first trench at or near a top of the first trench to form a vacuum gap
Data Source
AI summary
The present disclosure relates to a semiconductor device. The semiconductor device includes a semiconductor on an insulator (SOI) substrate having a bottom substrate, a buried oxide layer on the bottom substrate, and a semiconductor layer on the buried oxide layer. The semiconductor device also includes a first dielectric layer disposed on the semiconductor layer, a first contact structure extending from a top surface of the first dielectric layer through the semiconductor layer and the buried oxide layer and contacting the bottom substrate, and a first trench extending into the semiconductor layer. A width of the first trench is smaller than a width of the first contact structure. The first dielectric layer seals the first trench at or near the top of the first trench to form a vacuum gap.