Concave Contact Via Structure for Narrower Bottom Widths

Solution Overview

Problem

Conventional methods for patterning smaller feature sizes in semiconductor devices are time-consuming and costly, making it challenging to keep up with technological advances in device miniaturization.

Innovation Solution

The development of contact via structures with a concave profile in semiconductor devices, which are formed using a method involving a conductive feature, a dielectric layer, and a dielectric control layer to achieve electrical coupling with a conductive feature, allowing for narrower bottom widths without the need for advanced patterning equipment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If conventional photolithography patterning techniques are used to achieve smaller feature sizes, then device miniaturization is enabled, but the process becomes time-consuming and costly

Engineering Contradiction:

Improvefeature sizeVSAvoidpatterning process time

Core Design Contradiction:

Length of moving objectVSLoss of time

Solution Approach 1:

The contact via structure is divided into multiple segments: a first portion with a first width at the top and a second width at the bottom (narrower than the conductive feature), and a second portion with a third width (wider than the conductive feature). This segmentation allows the structure to be formed through a simplified two-step process (forming the first portion, then forming the second portion) rather than requiring complex advanced patterning techniques, thus reducing patterning time while achieving miniaturization

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The contact via structure utilizes vertical dimensionality by creating varying widths at different heights (first width at top, second width at bottom, third width at middle). This three-dimensional approach allows the structure to achieve smaller effective feature sizes for electrical coupling while the overall structure dimensions can be formed using conventional patterning, thereby reducing the time and cost associated with advanced patterning techniques

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Length of moving object

If conventional photolithography patterning techniques are used to achieve smaller feature sizes, then device miniaturization is enabled, but the cost increases

Engineering Contradiction:

Improvefeature sizeVSAvoidmanufacturing cost

Core Design Contradiction:

Length of moving objectVSEase of manufacture

Solution Approach 1:

The contact via structure is divided into multiple segments: a first portion with a first width at the top and a second width at the bottom (narrower than the conductive feature), and a second portion with a third width (wider than the conductive feature). This segmentation allows the structure to be formed through a simplified two-step process (forming the first portion, then forming the second portion) rather than requiring complex advanced patterning techniques, thus reducing patterning time while achieving miniaturization

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The contact via structure utilizes vertical dimensionality by creating varying widths at different heights (first width at top, second width at bottom, third width at middle). This three-dimensional approach allows the structure to achieve smaller effective feature sizes for electrical coupling while the overall structure dimensions can be formed using conventional patterning, thereby reducing the time and cost associated with advanced patterning techniques

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Manufacturing precision

If contact via structures with narrower bottom widths are formed, then transistor density increases, but conventional patterning methods cannot achieve the required precision

Engineering Contradiction:

Improvecontact via bottom width precisionVSAvoidpatterning process complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The contact via structure is divided into multiple segments: a first portion with a first width at the top and a second width at the bottom (narrower than the conductive feature), and a second portion with a third width (wider than the conductive feature). This segmentation allows the structure to be formed through a simplified two-step process (forming the first portion, then forming the second portion) rather than requiring complex advanced patterning techniques, thus reducing patterning time while achieving miniaturization

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The contact via structure utilizes vertical dimensionality by creating varying widths at different heights (first width at top, second width at bottom, third width at middle). This three-dimensional approach allows the structure to achieve smaller effective feature sizes for electrical coupling while the overall structure dimensions can be formed using conventional patterning, thereby reducing the time and cost associated with advanced patterning techniques

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS11776844B2Contact via structures of semiconductor devices

Publication Date: 2023.10.03 GLOBALFOUNDRIES SINGAPORE PTE LTD

AI summary

The embodiments herein relate to contact via structures of semiconductor devices and methods of forming the same. A semiconductor device is provided. The semiconductor device includes a substrate, a conductive feature over the substrate, and a contact via structure over and electrically coupling to the conductive feature. The contact via structure has a concave profile.