1. U of M Material Science Seagate Design Group
Alan Bagwell
Tony Lindert
Loc Nguyen
Greg Rayner
Industrial Mentor:
Dr. Vince Engelkes
Faculty Advisor:
Prof. C. Daniel Frisbie

2. Outline Company Overview Recording Technology
Reader and Writer Elements
Design Project

3. Seagate
Founded in 1979 by Alan Shugart and Finis Conner in Scotts Valley, California.
Public company in 1981 (NASDAQ: SGAT).
Now traded under NASDAQ: SXT
World’s leading provider of hard disc drives.
Approximately 54,000 employees in 28 worldwide locations.
Highest market share of hard drive sales; 33% of overall market.
FY2008: 182M drives shipped; revenue of $12.7B
Shipped billionth drive April 2008
January 5, 2009 – 3.5-inch 7200-RPM drive with an areal density of 329 Gigabits per square inch.

4. Seagate’s Global Presence
Springtown, N. Ireland
Minneapolis, MN
Fremont, Milpitas, Santa Clara, Scotts Valley, Sunnyvale, CA
Amsterdam, Netherlands
Paris, France
Beijing, China
Tokyo, Japan
Shrewsbury, MA
Wuxi, China
Suzhou, China
Delhi, India
Shanghai, China
Oklahoma City, OK
Bangkok & Korat, Thailand
Taiwan
Longmont, CO
Penang, Malaysia
Ang Mo Kio, Science Park & Woodlands, Singapore
Drives and Components
Regional HQ’s and Sales
Design
Customer Support
Seagate Services Headquarters
Seagate Confidential 4

5. Seagate in Minnesota Recording Heads Operation
Seagate’s internal and principal supplier of recording heads.
BLOOMINGTON, MN
Enterprise Drive Division
Develops the largest, fastest and most advanced enterprise disc drives in the world.
SHAKOPEE, MN
Seagate Confidential 5 5

6. R&D Investment (2008) $ Millions
Source: Seagate Market & Competitive Intelligence

7. Market Share Estimates
Total Market
Q3 FY08
132.3M Units
Q4 FY08
132.3M Units
Source: Seagate Market & Competitive Intelligence
Seagate Confidential 7

8. Hard Drive Overview
Platters store data in magnetically oriented grains
Actuator arm moves the head closer or farther from the platter center
Head contains reader/writer elements
Platter spins at up to 15,000 RPM
Logic board controls motion of actuator

9. Platter Construction Aluminum or glass/ceramic with metal sputter
Concentric circles divide it into tracks/cylinders (10,000+)
Radial lines divide it into sectors (often 63)
Tracks and sectors intersect to form blocks: typically 512 bytes per block

10. Total Data Capacity Data = Heads * Cylinders * Sectors * Bytes
Amount of platters can be increased
Data density ultimately comes down to how small the bits can be made before they become unreadable

11. Improving Data Density
Platter materials – thermal considerations
Perpendicular recording (2005)
Giant magnetoresistance (Nobel Prize 2007)
Actuator head sensitivity

12. Actuator Head (“Slider”)
Actuator head contains read/write elements
Key to increasing data storage density

13. Challenges for the Slider
Reader element must be made more sensitive in order to read smaller and more densely packed bits.
Writer, in turn, must be made stronger to compensate for smaller size in order to write smaller bits.
“Fly height” must be minimized to reduce error
Vince Engelkes, Seagate

14. Flying Height
Flying heights of 10 nm currently achieved (equivalent to 30 average sized atoms).
If the slider is too close to the surface, surface roughness leads to a decrease in reliability and product life.
Increasing the flying height leads to performance error.
Slider held above the disk surface by “Air Bearing”
Suspension
Slider
Air bearing
Vince Engelkes, Seagate

15. Fly Height Control Adaptive Clearance Control
Integrated heating element added to transducer.
In-drive algorithms adjust clearance between the reader/writer elements and disc.
Dr Marcus Mooney, Materials for Electronics, Seagate

17. Wafer Process Wafer Magnetic Recording Heads Wafer Fabrication
Creating a wafer (a group of heads) takes about 700 different manufacturing steps
80,000+ recording heads are built on a 200mm wafer
Wafer
Wafer Fabrication
Creation of electromagnet uses many processes
Photolithography
Electro-plating
Vacuum deposition
Vacuum milling
Chemical-Mechanical Polishing (CMP)
Wet etching
Metrology, Inspection & Electrical Test

18. Slider Construction
Aside from reader/writer fabrication, careful processing of the air bearing components of the slider is essential.
Air bearings are designed to control the fly height, pitch, roll, head-media spacing, and many other important specifications of the slider.
Techniques such as ion milling and photolithography are used
Dr Marcus Mooney, Materials for Electronics, Seagate

20. Head Materials

21. Design Project Increase areal density and product life. Market Need
More storage space
Reliability
Cheap
Project Need
Roughness and positioning precision of 2A (currently ~10A).
Possible materials change
Should not undergo phase changes up to ~250C.
Should not be react with neighboring materials
Similar or better properties
Reliable: 5+ years of warranties.
Ease of production/fabrication
Cost consideration

22. Q&A