Negative-Tapered Contact Layout to Prevent Gate Shorts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
As CMOS technology scales down, FinFET or nanosheet devices face interference and spacing issues with adjacent components, leading to shorts when forming contacts, particularly due to the shrinking size and closer proximity of devices.
Innovation Solution
A microelectronic device design featuring a contact with tapered sidewalls and a gate contact with inverse tapering, where the contact is formed using an angled reactive ion etching process to create a wider bottom section and narrower top section, ensuring sufficient spacing between the contact and the gate to prevent shorting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If devices are scaled down and placed closer together to increase density, then device integration is improved, but spacing between adjacent components deteriorates leading to shorts
Solution Approach 1:
The contact structure employs asymmetric tapering where the sidewalls are angled towards the gate contact, creating a non-uniform cross-sectional shape. This asymmetric geometry allows the contact to fit closer to the gate contact while maintaining adequate spacing, thus improving device integration density without compromising reliability
Solution Approach 2:
The solution transitions from a conventional vertical contact structure to a three-dimensional tapered structure with angled sidewalls. By modifying the contact geometry in multiple dimensions rather than simply reducing size, adequate spacing is maintained while achieving higher integration density
2Ease of manufacture
If conventional vertical contacts are used, then manufacturing is simple, but spacing to gate contact is insufficient causing shorts
Solution Approach 1:
The contact sidewall angle is changed from vertical (90 degrees) to a tapered angle, modifying the geometric parameters of the contact structure. This parameter change increases the horizontal spacing to the gate contact, preventing shorts while remaining compatible with standard semiconductor manufacturing processes
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 tapered contact design effectively prevents shorting between the source/drain contact and the gate contact by maintaining adequate spacing, enhancing reliability and preventing issues like soft leakage or dielectric breakdown.
Implementation Method 1
Forming a second trench by utilizing an angled reactive ion etching process to widen the first trench
Data Source
AI summary
A microelectronics device including a gate region located adjacent to a source/drain region. A contact located above the source/drain region, where the contact has a bottom section, a middle section and top section, wherein the sidewalls of the bottom section, the middle section, and the top section of the contact are tapered towards a center Y-axis of the contact. A gate contact located above the gate region, where the gate contact has tapered sidewalls towards a center Y-axis of the gate contact. The gate contact is adjacent to the contact. The tapering of the sidewalls of the gate contact is inverse to the tapering of the sidewalls of the contact.