| Author | Suttisak Nilchim |
| Note | A thesis submitted in partial fulfillment of the requirements for the
degree of Master of Science in
Microelectronics and Embedded Systems, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | Recently hard disk drive capacity has been increasing until almost reach the limit of
conventional recording (Perpendicular Magnetic Recording: PMR). Moving forward there
are a few of new technologies under development to increase hard disk drive capacity
beyond 1Tb/Inch2. SMR is one of the intermediate solutions to achieve higher capacity in
hard disk drive. The reason is SMR can be done with conventional head and medium
design. Only some changes required for SMR which minimum compare to other three
technologies. However due to the track will be heavy overlapping in SMR, the write
encroachment will become the main problem. To maintain the hard disk drive quality and
reliability, this thesis has been conducted. The thesis will enhance the write encroachment
detection by using previous track PES as a feed forward to current PES and use that
information to detect write encroachment in SMR. The threshold limit will come from
calibration method which will perform write encroachment simulation to get the optimum
threshold for detection part. The locations which mark as write encroachment will become
defective location which will not be accessible by end user. In summary the method to
calibrate for write encroachment threshold is working correctly as compare with the
feedback from read parameters. Also the detection method worked well with calibrated
threshold. The write encroachment defect can be detected with this thesis methodology and
defective area has been proven as defect based on read back parameters which EM (Error
Margin) OTRC (Off-Track Read Capability) and LDPC (Low Density Parity Check) result |
| Year | 2015 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Industrial Systems Engineering (DISE) |
| Academic Program/FoS | Microelectronics (ME) |
| Chairperson(s) | Huynh Trung Luong ; |
| Examination Committee(s) | Afzulpurkar, Nitin ;Mongkol Ekpanyapong;Bundit Jangsrisert; |
| Scholarship Donor(s) | Western Digital ;AIT Fellowship; |