| Author | Larry Tan Chun Hai |
| Note | A thesis submitted in partial fulfillment of the requirements for the
degree of Master of Science in
Mechatronics, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | In hard disk drives, there is always a need to increase areal density or to pack more data per area on a given recording media. Hard disk areal density growth is essential for storing digital contents. Traditional Perpendicular Magnetic Recording (PMR) has nearly reached its threshold in terms of areal density growth. A potential technology to replace PMR is the
Heat Assisted Magnetic Recording, HAMR.
HAMR requires Laser Diode bonding on a heat sink called submount to the slider body. The submount is then attached to the slider body through a soldering process. The bonding of the submount to the slider body approximates flip chip bonding. Unfortunately, the bonded submount also deforms the slider body. Bonding requires heating to the solder. Differences
in the coefficient of thermal expansion between the slider body and submount causes the slider body to expand 3 times more than the submount during heating. When cooling, the rigid body of the submount and the harden solder prevents the slider from shrinking back to
its original form. Therefore, internal stresses in the slider body were created. This stress than creates a momen that bows the slider body downwards. The deformed slider body would affect the slider flying stability in the hard disk during reading and writing. This thesis proposes 2 solutions to minimize the camber of the slider body ; by reducing the solder pad width and changing the composition of the solder joints. The smaller the solder width, the lower the changes in the slider camber. The higher percentage the AuSn composition is formed in the solder joint, the less stiff the joint. This allows the slider body to retract back
its original form after bonding. Therefore, the camber of the slider body is less. |
| Year | 2016 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Industrial Systems Engineering (DISE) |
| Academic Program/FoS | Microelectronics (ME) |
| Chairperson(s) | Ekpanyapong, Mongkol; |
| Examination Committee(s) | Bohez, Erik L.J.;Lim, Chee Kheng; |
| Scholarship Donor(s) | Western Digital (Thailand) Co., Ltd.;AIT Fellowship; |