IC Pad Lead-Out Layout for Reliable Ultrasonic Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing integrated circuit devices face challenges in efficiently leading out wiring from pads without overlapping, which can result in short circuits or wire-breakages during ultrasonic bonding, especially when the circuit overlaps the pad in a plan view.
Innovation Solution
The integrated circuit device features a pad with a longitudinal and lateral direction, where lead-out wiring is led out from the outer edge along the lateral direction, and a via group electrically couples the wiring without overlapping the pad, allowing for effective electrical coupling while reducing the device's area and preventing damage from ultrasonic vibration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If the circuit is disposed to overlap the pad in plan view to reduce device area, then area utilization is improved, but the risk of short circuits and wire-breakages during ultrasonic bonding increases
Solution Approach 1:
The lead-out wiring is led out from the outer edge on the longitudinal side of the pad along the lateral direction, transitioning the wiring path to a different spatial dimension that avoids the ultrasonic vibration zone. This dimensional change allows the circuit to overlap the pad for area reduction while the wiring bypasses the harmful vibration effects through a different spatial route.
Solution Approach 2:
The electrical coupling is divided into two separate components: the lead-out wiring that connects to the pad edge and the via group that connects to the circuit wiring. This segmentation allows each component to be optimally positioned - the lead-out wiring away from the pad center to avoid vibration, and the via group away from the pad in plan view to prevent short circuits while maintaining electrical connectivity.
2Length of moving object
If lead-out wiring is led out from the pad center, then wiring length is reduced, but the wiring is susceptible to damage from ultrasonic vibration
Solution Approach 1:
The lead-out wiring is extracted from the traditional center-based connection and repositioned to connect to the outer edge of the pad along the longitudinal side. This extraction removes the wiring from the high-stress ultrasonic vibration zone at the pad center, protecting it from damage while the via group handles the connection to the overlapped circuit.
3Device complexity
If the via group is positioned to overlap the pad, then electrical coupling is simplified, but short circuits occur during ultrasonic bonding
Solution Approach 1:
The via group acts as an intermediary electrical coupling component that is deliberately positioned away from the pad in plan view. This intermediary position allows the via group to connect the lead-out wiring to the circuit wiring without being in the direct path of ultrasonic bonding, thus preventing short circuits while maintaining electrical functionality.
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 configuration enables reduced area utilization, prevents short circuits and wire-breakages, and enhances the reliability of the integrated circuit device by aligning the pad's shape with the ultrasonic vibration direction and using a via group to securely couple the lead-out wiring.
Implementation Method 1
the terminal provided on the surface of the package and the bump formed on the pad are coupled by ultrasonic bonding in which the longitudinal direction of the pad serves as a vibration direction
Data Source
AI summary
The integrated circuit device includes: a pad that has a shape having a longitudinal direction and a lateral direction; a circuit that overlaps the pad in a plan view, and that is electrically coupled to the pad; a lead-out wiring that is led out from an outer edge on a longitudinal side of the pad along the lateral direction of the pad; and a via group that electrically couples the lead-out wiring and a wiring of the circuit and that does not overlap the pad in the plan view.