Head Gimbal Assembly Top Surface Bonding for Shock Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing interconnection methods between head sliders and suspensions in disk drives are laborious, prone to damage from shock stress, and result in attitude variations that degrade flying performance and data reading/writing efficiency due to insufficient space for bonding connections and lack of attitude control.
Innovation Solution
A head gimbal assembly with an attitude control layer between the head slider and suspension, featuring slider and flexure electrical bonding pads for secure mechanical and electrical connection, along with a trace pattern and insulation layer to ensure stable pitch and roll attitudes, reducing flying height variations and improving data access performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If bonding pads are arranged on the trailing surface of the head slider, then electrical connection is achieved, but the available space becomes insufficient as slider size decreases
Solution Approach 1:
The patent moves the bonding pads from the trailing surface to the top surface of the head slider, utilizing a different spatial dimension. This allows the bonding pads to be arranged on a larger area without increasing the slider's footprint, effectively resolving the space constraint while maintaining electrical connection capability.
2Reliability
If solder or metal balls are used for bonding, then electrical connection is established, but the connection becomes vulnerable to shock stress and rotation
Solution Approach 1:
The patent introduces an intermediary structure (the top surface mounting arrangement with expanded bonding area) between the head slider and flexure that distributes mechanical stress and reduces the direct transmission of shock and rotation forces to the bonding pads, thereby protecting the electrical connection while maintaining reliability.
3Strength
If multiple bonding processes are used for mechanical and electrical connection, then strong bonding performance is achieved, but the assembly process becomes complicated and time-consuming
Solution Approach 1:
The patent combines the mechanical support function and electrical connection function into a single integrated bonding structure on the top surface. By arranging bonding pads on the top surface where they can serve both mechanical attachment and electrical connection purposes simultaneously, the need for separate bonding processes is eliminated, simplifying the assembly process while maintaining bonding strength.
4Productivity
If head slider size is reduced to decrease cost, then more sliders can be produced per wafer, but the space for bonding connections becomes insufficient
Solution Approach 1:
The patent enables continued miniaturization of the head slider by moving the bonding pads to the top surface, which provides ample space even on reduced-size sliders. This dimensional relocation allows cost reduction through increased productivity while maintaining sufficient bonding connection space.
Data Source
AI summary
A head gimbal assembly (HGA) has an improved interconnection between a head slider and a suspension of the HGA. The interconnection is achieved by using a reverse surface of an air bearing surface of the head slider as bonding surface to provide more space for arranging more slider electrical bonding pads thereon. The head slider is mechanically and electrically connected to the suspension at the bonding surface to have good performance on shocking conditions. The suspension further has an attitude control layer located between the head slider and the suspension. The attitude control layer serves as a datum plate for the head slider lying thereon and supporting the head slider so as to ensure the head slider a good attitude and reduce variation of slider flying height. The present invention also discloses a magnetic disk drive with the improved HGA and a fabricating method for the HGA.