Inertial Sensor Eutectic Bonding With Dummy Pattern Stabilization
Solution Overview
Problem
Existing inertial sensors face issues with bonding strength and reliability due to non-uniform Ge concentration in AlGe eutectic layers, leading to potential deterioration of bonding strength and interference with sensor elements.
Innovation Solution
A configuration involving a metal eutectic layer with alternating face-centered cubic and diamond structures, combined with dummy patterns to stabilize the bonding region and prevent protrusion into the sensor element, ensuring uniform height and high bonding strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If AlGe eutectic bonding material is used with non-uniform Ge concentration, then bonding process is simplified, but bonding strength deteriorates
Solution Approach 1:
The patent applies local quality by creating distinct regions within the bonding structure: a first region with AlGe eutectic layer having uniform Ge concentration for optimal bonding strength, and a second region with AlGe eutectic layer having different Ge concentration for controlling bonding characteristics. This spatial variation in material composition allows simultaneous optimization of bonding strength and manufacturing simplicity.
2Device complexity
If eutectic bonding is performed without dummy pattern, then device structure is simpler, but bonding material may protrude and affect sensor element
Solution Approach 1:
The dummy pattern is formed in advance before the eutectic bonding process. This preliminary structure serves as a physical barrier that prevents bonding material from protruding into the sensor element region during bonding. The dummy pattern is strategically positioned to intercept any excess bonding material flow before it can reach the sensitive sensor element.
3Quantity of substance
If interconnection extraction causes unevenness in bonding region, then electrical connectivity is achieved, but bonding uniformity deteriorates
Solution Approach 1:
The patent addresses bonding uniformity by implementing local quality control through the dummy pattern structure. The dummy pattern is specifically designed to compensate for unevenness caused by interconnection extraction, providing localized support and reference planes that ensure uniform bonding pressure and heat distribution across the bonding region, thereby maintaining manufacturing precision despite the presence of extracted interconnections.
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 provides a robust bonding structure with high reliability and stability, preventing interference with sensor operation while maintaining electrical connectivity and ensuring long-term performance.
Implementation Method 1
a metal eutectic layer configured to bond the base body and the lid body to each other in a bonding region
Data Source
AI summary
An inertial sensor or an electronic component includes a base body, a lid body, a functional element disposed between the base body and the lid body, a metal eutectic layer configured to bond the base body and the lid body to each other in a bonding region located on a periphery of the functional element, a plurality of interconnections which passes through the bonding region to be coupled to the functional element, and a dummy pattern disposed in the bonding region so as to overlap the metal eutectic layer at a same height as the interconnections.