Substrate Stepped Structures for Space-Efficient Interconnection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for interconnecting stacked substrates, particularly those made of non-etchable materials like lithium tantalate or lithium niobate, are labor-intensive and costly, and lack a space-saving solution suitable for microelectromechanical structures and components utilizing surface or bulk acoustic waves.
Innovation Solution
A method involving the formation of stepped structures on substrates with conductor tracks that allow for substrate bonding and subsequent division into pieces, enabling the creation of accessible conductor tracks for further connections, facilitating the stacking and electrical interconnection of multiple substrates in a space-saving manner.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If via through-plating is used for non-etchable substrates, then electrical connection through substrate is achieved, but manufacturing cost and labor intensity increase significantly
Solution Approach 1:
The substrate is divided into a first main area and a second main area by severing along predetermined lines. This segmentation allows conductor tracks to be formed on different surfaces and connected through stepped structures, providing an alternative to through-plating for achieving electrical connections in non-etchable substrates without the associated high costs and labor intensity.
Solution Approach 2:
Conductor tracks are extended from the first main area to the second main area by forming stepped structures and routing conductor tracks through the side walls of the substrate. This three-dimensional routing approach replaces the vertical through-plating method, achieving electrical connection while avoiding the costly through-plating process in non-etchable materials.
2Reliability
If wire bonding is used for interconnection, then electrical connection is achieved, but space consumption increases
Solution Approach 1:
The mechanical substrate connection and electrical conductor track connection are merged into a single integrated structure. The stepped structures and conductor tracks are formed directly on the substrate during the same manufacturing process, eliminating the need for separate wire bonding operations and reducing overall space consumption.
Solution Approach 2:
Instead of using wire bonding that extends outward in three-dimensional space, the conductor tracks are routed through the substrate itself by forming stepped structures and extending tracks along side walls. This internal routing through the substrate thickness dimension reduces external space requirements compared to wire bonding.
3Volume of moving object
If substrates are connected without housing, then space efficiency is improved, but manufacturing complexity increases for achieving both mechanical and electrical connection
Solution Approach 1:
Stepped structures are formed on the substrate surface before the substrate is severed into final pieces. This preliminary action allows conductor tracks to be properly routed and connected across what will become separate substrate pieces, simplifying the overall manufacturing process by establishing the connection path early rather than requiring complex post-assembly operations.
Solution Approach 2:
The substrate serves multiple functions: it provides mechanical support, contains integrated circuits, and acts as the medium for forming conductor tracks that achieve electrical connection. The stepped structures and conductor track system provide both mechanical alignment features and electrical connection paths, reducing the need for separate housing and connection components.
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 method enables cost-effective, space-efficient interconnection of substrates, suitable for microelectromechanical structures and components, allowing for the formation of cavity housings and enabling the stacking of multiple substrates while maintaining mechanical and electrical connectivity.
Implementation Method 1
The first substrate is connected on the side of its first main area to a further substrate or to a stack of further substrates, preferably by substrate bonding
Data Source
AI summary
A plurality of unpackaged substrates connected to one another is disclosed. The stepped structures on and/or in a first main area of a first substrate include a plurality of integrated circuits. The stepped structures run between the integrated circuits. The first conductor tracks extend from at least some contact connections of the respective integrated circuits as far as the stepped structures. The first substrate is connected on the side of the first main area to a further substrate. The first substrate is severed from a second main area opposite to the first main area such that the first substrate is divided into a plurality of substrate pieces. Each substrate piece has one of the integrated circuits. The first conductor tracks are accessible in interspaces between the substrate pieces. The second conductor tracks are formed from the second main area. At least some of the second conductor tracks lead from the second main area over side walls of the substrate pieces as far as the first conductor tracks.