Semiconductor Device Multi-Layered Wiring Leakage Current Reduction

Solution Overview

Problem

As semiconductor elements continue to downscale, the increasing aspect ratio and decreasing intervals between circuit components, such as wirings, lead to higher leakage currents due to diffusion of conductive materials, which existing technologies struggle to mitigate effectively.

Innovation Solution

A semiconductor device design featuring an interlayer insulating film with varying densities and a via structure that reduces leakage by increasing the distance between the via and lower wiring, achieved through a method involving the formation of a first portion with a higher density and a second portion with a lower density in the interlayer insulating film, allowing for controlled etching and reduced diffusion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the interval between wirings is decreased to achieve higher integration, then the integration density is improved, but leakage current increases due to diffusion of conductive materials

Engineering Contradiction:

Improveintegration densityVSAvoidleakage current

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The interlayer insulating film is divided into two portions with different densities: a first portion with higher density near the lower wiring and a second portion with lower density near the upper wiring. This local quality variation creates different etch resistance zones that prevent conductive material diffusion while maintaining tight wiring spacing for high integration.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The density parameter of the interlayer insulating film is changed across different regions. The first portion has a higher density providing greater etch resistance to prevent diffusion, while the second portion has lower density allowing controlled etching. This parameter change enables the film to simultaneously prevent leakage and support wiring formation.

Inventive Principle:

Principle #35Parameter changes

2Length of moving object

If the aspect ratio of wirings is increased to achieve down-scaling, then the miniaturization is improved, but manufacturing precision becomes more difficult due to increased leakage risks

Engineering Contradiction:

Improvewiring dimensionsVSAvoidleakage control

Core Design Contradiction:

Length of moving objectVSManufacturing precision

Solution Approach 1:

The interlayer insulating film is divided into two portions with different densities: a first portion with higher density near the lower wiring and a second portion with lower density near the upper wiring. This local quality variation creates different etch resistance zones that prevent conductive material diffusion while maintaining tight wiring spacing for high integration.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The interlayer insulating film is prepared in advance with a density gradient structure before wiring formation. The first portion with higher density is positioned to provide etch resistance against potential diffusion paths, preventing leakage issues before they can occur during subsequent manufacturing steps.

Inventive Principle:

Principle #10Preliminary action

3Ease of manufacture

If a uniform density interlayer insulating film is used to simplify manufacturing, then the ease of manufacture is improved, but leakage current increases due to insufficient diffusion barrier

Engineering Contradiction:

Improvefilm formation simplicityVSAvoidleakage current

Core Design Contradiction:

Ease of manufactureVSObject-generated harmful factors

Solution Approach 1:

The interlayer insulating film is divided into two portions with different densities: a first portion with higher density near the lower wiring and a second portion with lower density near the upper wiring. This local quality variation creates different etch resistance zones that prevent conductive material diffusion while maintaining tight wiring spacing for high integration.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The interlayer insulating film functions as a composite structure with two portions having different densities but same material composition. This composite approach provides both etch resistance (first portion) and wiring formation capability (second portion) within a single film layer, preventing leakage without requiring multiple separate films.

Inventive Principle:

Principle #40Composite materials

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 solution effectively reduces leakage currents by increasing the distance between the via and lower wiring, thereby minimizing diffusion and enhancing the durability and adhesion of the interlayer insulating film, while maintaining efficient connectivity between circuit components.

Implementation Method 1

a first etch rate of the first portion of the interlayer insulating film is smaller than a second etch rate of the second portion of the interlayer insulating film

Methodology Applied

Scientific EffectEtching:

Data Source

PatentUS10825766B2Semiconductor device with multi-layered wiring and method for fabricating the same

Publication Date: 2020.11.03 SAMSUNG ELECTRONICS CO LTD

AI summary

A semiconductor device includes a lower wiring, an interlayer insulation film above the lower wiring and including a first portion having a first density, and a second portion on the first portion, the first portion and the second portion having a same material, and the second portion having a second density smaller than the first density, an upper wiring in the second portion of the interlayer insulating film, and a via in the first portion of the interlayer insulating film, the via connecting the upper wiring and the lower wiring.