Low-k Film Pad Reinforcement for Semiconductor Cracking

Solution Overview

Problem

Semiconductor devices with low dielectric constant interlayer insulation films face issues of cracking and film-peeling due to their low mechanical strength, which complicates production and increases costs, especially when bonding processes are performed.

Innovation Solution

Incorporating a harder material under the pad part within the low dielectric constant film layer, specifically forming dummy patterns with higher hardness than the low dielectric constant film, to prevent cracking and simplify the manufacturing process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a porous insulation film with low dielectric constant is applied to reduce signal delay, then signal transmission performance is improved, but mechanical strength decreases causing cracking during bonding

Engineering Contradiction:

Improvesignal transmission performanceVSAvoidmechanical strength

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent applies different material properties to different regions: the porous low-k insulation film is used in regions where signal transmission is critical, while a harder support film is applied specifically in the pad part region where mechanical strength is needed during bonding. This local differentiation resolves the contradiction by allowing each region to have the property it needs most.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent creates a composite structure by stacking the porous insulation film and the harder support film in different layers. The support film with higher hardness provides mechanical reinforcement during bonding, while the porous insulation film maintains low dielectric constant for signal transmission, combining the benefits of both material types.

Inventive Principle:

Principle #40Composite materials

2Reliability

If a porous insulation film with low dielectric constant is applied to reduce signal delay, then signal transmission performance is improved, but adhesiveness deteriorates causing film-peeling during probing

Engineering Contradiction:

Improvesignal transmission performanceVSAvoidadhesiveness

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent applies different material properties to different regions: the porous low-k insulation film is used in regions where signal transmission is critical, while a harder support film is applied specifically in the pad part region where mechanical strength is needed during bonding. This local differentiation resolves the contradiction by allowing each region to have the property it needs most.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent creates a composite structure by stacking the porous insulation film and the harder support film in different layers. The support film with higher hardness provides mechanical reinforcement during bonding, while the porous insulation film maintains low dielectric constant for signal transmission, combining the benefits of both material types.

Inventive Principle:

Principle #40Composite materials

3Reliability

If dummy patterns are formed in every layer of insulation films under the pad part to prevent cracking and film-peeling, then reliability is improved, but device complexity increases and production cost rises

Engineering Contradiction:

Improvebonding reliabilityVSAvoidprocess complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies different material properties to different regions: the porous low-k insulation film is used in regions where signal transmission is critical, while a harder support film is applied specifically in the pad part region where mechanical strength is needed during bonding. This local differentiation resolves the contradiction by allowing each region to have the property it needs most.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent extracts the dummy pattern formation step from the manufacturing process by replacing it with a support film that inherently provides the necessary mechanical strength. This eliminates the need for additional dummy patterns while maintaining bonding reliability, thus reducing process complexity.

Inventive Principle:

Principle #2Taking out (Extraction)

Data Source

PatentUS8004086B2Semiconductor device

Publication Date: 2011.08.23 RENESAS ELECTRONICS CORP

AI summary

The present invention provides a semiconductor device capable of preventing occurrence of cracking and the like, taking a large area, where wiring and the like that function as elemental devices can be arranged, within a plurality of interlayer insulation films, and reducing production cost. The semiconductor device according to the present invention has a low dielectric constant film having a dielectric constant of not less than 2.7. In the low dielectric constant film and the like, materials (e.g., a first dummy pattern, a second dummy pattern) with a larger hardness than that of the low dielectric constant film are formed at a part under a pad part.