Vibrator IC Layout for Bonding Stress-Sensitive Circuit Placement

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In wafer level packaging (WLP) type vibrator devices, stress applied during the bonding process can affect the circuit characteristics of the integrated circuit, as the layout design typically does not consider the stress generated in the base.

Innovation Solution

The vibrator device includes a base with a semiconductor substrate having an integrated circuit on one surface, a vibration element electrically coupled to the integrated circuit, and a lid with a recess for the vibration element. The integrated circuit is arranged with specific regions for different circuit elements, where the first circuit elements with lower stress sensitivity are placed in regions experiencing higher stress, and the second circuit elements with higher stress sensitivity are placed in regions experiencing lower stress.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the integrated circuit is disposed at the second surface of the base without considering stress distribution, then the device structure is simple and manufacturing is easy, but the circuit characteristics are affected by stress during bonding

Engineering Contradiction:

Improveease of manufactureVSAvoidcircuit characteristics

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent divides the second surface of the base into multiple regions with different stress characteristics. Circuit elements are selectively disposed in specific regions based on their stress sensitivity. Low stress-sensitive elements are placed in high stress regions, while high stress-sensitive elements are placed in low stress regions, optimizing both manufacturing simplicity and circuit reliability.

Inventive Principle:

Principle #3Local quality

2Strength

If the vibration element is accommodated in a recess of the lid with bonding portion, then the vibration element is protected and electrically coupled to the integrated circuit, but stress is generated in the base during bonding process

Engineering Contradiction:

Improveprotection of vibration elementVSAvoidstress in base

Core Design Contradiction:

StrengthVSStress or pressure

Solution Approach 1:

The patent recognizes that different regions of the base experience different stress levels during the bonding process. By analyzing the stress distribution pattern, the patent strategically places circuit elements in regions with appropriate stress characteristics, thereby mitigating the harmful effects of bonding-induced stress on circuit performance.

Inventive Principle:

Principle #3Local quality

3Area of stationary object

If the integrated circuit occupies the entire second surface, then the arrangement area is maximized, but stress sensitivity affects circuit characteristics

Engineering Contradiction:

Improvearrangement areaVSAvoidcircuit characteristics

Core Design Contradiction:

Area of stationary objectVSReliability

Solution Approach 1:

The patent partitions the second surface into multiple regions with different stress characteristics and selectively places circuit elements in specific regions. This approach allows the integrated circuit to occupy a large area while ensuring that stress-sensitive elements are positioned in low stress regions, thereby maintaining both high arrangement area and circuit reliability.

Inventive Principle:

Principle #3Local quality

4Device complexity

If circuit elements are randomly disposed on the second surface, then layout design is simple, but stress sensitivity causes deterioration in circuit characteristics

Engineering Contradiction:

Improvelayout designVSAvoidcircuit characteristics

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent categorizes circuit elements based on their stress sensitivity and assigns them to specific regions of the second surface accordingly. This systematic approach provides clear layout design guidelines that are simpler than random placement, as designers only need to follow the region-based placement rules to ensure circuit reliability under stress conditions.

Inventive Principle:

Principle #3Local quality

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

This arrangement effectively minimizes the impact of stress on the circuit characteristics, allowing for a larger arrangement area of the integrated circuit and preventing deterioration in circuit characteristics, thus enabling the implementation of small-sized and highly functional vibrator devices.

Implementation Method 1

having an end surface of the side wall bonded to the first surface at a bonding portion

Methodology Applied

Scientific EffectBonding: Adhesive

Data Source

PatentUS12294333B2Vibrator device

Publication Date: 2025.05.06 SEIKO EPSON CORP

AI summary

A vibrator device includes: a base having an integrated circuit disposed at a second surface; a vibration element; and a lid having an end surface of a side wall bonded to a first surface of the base at a bonding portion. The integrated circuit includes a first circuit and a second circuit, the first circuit includes a plurality of first circuit elements disposed in a first region ARA, and the second circuit includes a second circuit element disposed in a second region ARB. At this time, the following relations are established.{1-L⁢1⁢A/WX}≤0.95⁢{1-L⁢2⁢A/WX}≤0.95⁢{1-L⁢3⁢A/WY}≤0.95⁢{1-L⁢4⁢A/WY}≤0.95⁢{1-L⁢1⁢B/WX}≤0.8⁢{1-L⁢2⁢B/WX}≤0.8⁢{1-L⁢3⁢B/WY}≤0.8⁢{1-L⁢4⁢B/WY}≤0.8