Air Gap Structures Reduce Parasitic Capacitance in Semiconductor Interconnects
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The miniaturization of semiconductor devices leads to increased complexity in manufacturing, resulting in higher parasitic capacitance and power consumption due to increased capacitive coupling between conductive elements, which complicates integration and affects device performance.
Innovation Solution
A semiconductor device structure is developed with air gap structures between conductive features, where a dielectric layer is formed with a portion separated from the substrate by an air gap, reducing parasitic capacitance and incorporating metal plugs and doped regions, and a method involving energy removable layers and thermal treatment to create these air gaps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If semiconductor devices are miniaturized to increase integration, then device functionality and circuit density are improved, but parasitic capacitance and power consumption increase
Solution Approach 1:
The patent introduces air gap structures (porous regions) between adjacent conductive elements in the semiconductor device. These air gaps reduce the dielectric constant of the surrounding medium, thereby reducing parasitic capacitance between conductors. This allows for continued miniaturization and increased integration density while mitigating the associated increase in power consumption due to capacitive coupling.
2Productivity
If semiconductor devices are miniaturized to increase integration, then device functionality is improved, but manufacturing complexity increases
Solution Approach 1:
The air gap structures are formed as part of the existing semiconductor manufacturing process flow, utilizing preliminary patterning and deposition steps that are already in place for creating conductive interconnect structures. By integrating air gap formation into the existing manufacturing sequence rather than adding separate complex steps, the patent achieves reduced parasitic capacitance while minimizing increases in manufacturing complexity.
3Productivity
If conductive elements are placed closer together to increase density, then integration is improved, but capacitive coupling between elements increases
Solution Approach 1:
The patent strategically positions air gap structures (porous regions) between adjacent conductive elements such as bit lines, word lines, and contacts. These air gaps create regions of lower dielectric constant that reduce the electric field coupling between conductors, thereby reducing parasitic capacitance and allowing conductive elements to be placed closer together without proportionally increasing capacitive coupling.
Solution Approach 2:
The air gap structures act as intermediary regions between adjacent conductive elements. These porous regions serve as electrical isolators that reduce the capacitive interaction between conductors while maintaining physical proximity for high-density integration. The air gaps function as mediators that allow close spacing without direct capacitive coupling.
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 air gap structures effectively reduce parasitic capacitance and power consumption, improving device performance and yield rate by minimizing capacitive coupling and signal delay.
Implementation Method 1
a first portion of the dielectric layer between the first metal plug and the second metal plug is separated from the semiconductor substrate by a first air gap
Implementation Method 2
performing a thermal treating process to transform the energy removable layer into an air gap structure
Data Source
AI summary
The present disclosure provides a method for preparing a semiconductor device structure. The method includes forming a first metal plug, a second metal plug, a third metal plug, and a fourth metal plug over a semiconductor substrate; forming an energy removable liner covering the first metal plug, the second metal plug, the third metal plug, and the fourth metal plug; performing an etching process to remove a portion of the energy removable layer from the substrate, while remaining an energy removable block between the first metal plug and the second metal plug in the cell region; forming a dielectric layer covering the energy removable block and the first metal plug, the second metal plug, the third metal plug, and the fourth metal plug; performing a thermal treating process to transform the energy removable layer into a first air gap structure including a first air gap enclosed by liner layer.