Method for shaping pole pieces of magnetic heads by chemical mechanical polishing
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Jan 21, 2003
Grant Date -
N/A
app pub date -
Feb 15, 2000
filing date -
Feb 15, 2000
priority date (Note) -
Expired
status (Latency Note)
![]() |
A preliminary load of PAIR data current through [] has been loaded. Any more recent PAIR data will be loaded within twenty-four hours. |
PAIR data current through []
A preliminary load of cached data will be loaded soon.
Any more recent PAIR data will be loaded within twenty-four hours.
![]() |
Next PAIR Update Scheduled on [ ] |

Importance
|
US Family Size
|
Non-US Coverage
|
Patent Longevity
|
Forward Citations
|
Abstract
The thin film magnetic head of the present invention includes an improved P2 pole tip/yoke interface structure. The interface structure includes yoke material that is formed in a concave curved shape at the interface between the P2 pole tip and the yoke, such that a right angle interface between the P2 pole tip and the yoke is eliminated. The process for forming the P2 pole tip/yoke interface includes a second CMP polishing step that is performed on the surface of the write head wafer subsequent to the plating of the P2 pole tip thereon, and subsequent to a first CMP step. This second CMP step utilizes a relatively soft polishing pad and an acidic polishing slurry having a pH within the range of approximately 1 to approximately 5, and preferably approximately 2.5. The acidic polishing slurry contains a chemical agent which preferentially attacks the P2 pole tip material, such that the second CMP step results in the recession of the upper surface of the P2 pole tip relative to the dielectric layer surrounding it, as well as the significant rounding of the upper edges of the dielectric trench in which the P2 pole tip is formed. Thereafter, when the yoke is plated onto the P2 pole tip the rounded upper edges of the dielectric trench result in a concave curved interface between the yoke and the P2 pole tip. The resulting P2 pole tip/yoke interface possesses improved magnetic flux flow control properties and results in decreased side writing. Greater track per inch areal data storage results from the reduced side writing of the improved write head.
First Claim
Family
- 15 United States
- 10 France
- 8 Japan
- 7 China
- 5 Korea
- 2 Other
Patent Owner(s)
| Patent Owner | Address | |
|---|---|---|
| HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B V | AMSTERDAM AMSTERDAM NORTH HOLLAND |
International Classification(s)
Inventor(s)
| Inventor Name | Address | # of filed Patents | Total Citations |
|---|---|---|---|
| Lahiri, Ashok | Mainz, DE | 81 | 1249 |
| Lee, Edward Hin Pong | San Jose, CA | 100 | 1054 |
| Lee, Eric James | San Jose, CA | 12 | 110 |
| Xu, Hong | San Jose, CA | 259 | 3625 |
Cited Art Landscape
- No Cited Art to Display

Patent Citation Ranking
Forward Cite Landscape
- No Forward Cites to Display

Maintenance Fees
| Fee | Large entity fee | small entity fee | micro entity fee | due date |
|---|
| Fee | Large entity fee | small entity fee | micro entity fee |
|---|---|---|---|
| Surcharge after expiration - Late payment is unavoidable | $700.00 | $350.00 | $175.00 |
| Surcharge after expiration - Late payment is unintentional | $1,640.00 | $820.00 | $410.00 |
Full Text
Legal Events
Matter Detail
Update Public Data
Dismiss
Edit
Save
Renewals Detail
Edit
Save
Note
The template below is formatted to ensure compatibility with our system.
Provide tags with | separated like (tags1|tags2).
Maximum length is 128 characters for Customer Application No
Mandatory Fields * - 'MatterType','AppType','Country','Title','SerialNo'.
Acceptable Date Format - 'MM/DD/YYYY'.
Acceptable Filing/App Types -
- Continuation/Divisional
- Original
- Paris Convention
- PCT National
- With Priority
- EP Validation
- Provisional Conversion
- Reissue
- Provisional
- Foreign Extension
Acceptable Status -
- Pending
- Abandoned
- Unfiled
- Expired
- Granted
Acceptable Matter Types -
- Patent
- Utility Model
- Supplemental Protection Certificate
- Design
- Inventor Certificate
- Plant
- Statutory Invention Reg
Advertisement
Advertisement
Advertisement
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Success
E-mail has been sent successfully.
Failure
Some error occured while sending email. Please check e-mail and try again!
PAIR load has been initiated
A preliminary load of cached data will be loaded soon. Current PAIR data will be loaded within twenty four hours.
File History PDF
Thank you for your purchase! The File Wrapper for Patent Number 6510022 will be available within the next 24 hours.
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully
Important Notes on Latency of Status data
Please note there is up to 60 days of latency in this Status indicator for certain status conditions. You can obtain up-to-date Status indicator readings by ordering PAIR for the file.
An application with the status "Published" (which means it is pending) may be recently abandoned, but not yet updated to reflect its abandoned status. However, an application filed less than one year ago is unlikely to be abandoned.
A patent with the status "Granted" may be recently expired, but not yet updated to reflect its expired status. However, it is highly unlikely a patent less than 3.5 years old would be expired.
An application with the status "Abandoned" is almost always current, but there is a small chance it was recently revived and the status not yet updated.
Important Note on Priority Date data
This priority date is an estimated earliest priority date and is purely an estimation. This date should not be taken as legal conclusion. No representations are made as to the accuracy of the date listed. Please consult a legal professional before relying on this date.
We are sorry but your current selection exceeds the maximum number of portfolios (0) for this membership level. Upgrade to our Level for up to -1 portfolios!.
