Method for making a semiconductor package with the distance between a lead frame die pad and heat spreader determined by the thickness of an intermediary insulating sheet
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Aug 18, 1992
Grant Date -
N/A
app pub date -
Dec 17, 1990
filing date -
Dec 17, 1990
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
A lead frame and die sub-assembly is first manufactured by a conventional method including bonding a die to the die attach pad of a lead frame and connecting wires between the die and the lead frame fingers. The sub-assembly is stacked first adjacent a dielectric plastic sheet that is in turn stacked against a metal heat spreader block. The dielectric sheet has a centrally located hole registered with the die attach pad. A dollop of an uncured resin is dispensed in the gap between the die attach pad and block. This assembly is compressed between two hot platens whereby the lead fingers, dielectric sheet and the block are bonded together and the resin dollop is flattened to a controlled thickness, namely the thickness of the dielectric sheet. The thickness of the dielectric sheet controls the flattened thickness of the cured resin dollop. After the platens are withdrawn, the local portion of the lead frame having been bonded in the stack is then put into a mold and the stack assembly encapsulated in a thermosetting resin to produce the semiconductor package.

First Claim
Family

- 15 United States
- 10 France
- 8 Japan
- 7 China
- 5 Korea
- 2 Other
Patent Owner(s)
Patent Owner | Address | |
---|---|---|
ALLEGRO MICROSYSTEMS INC | 1048 SUNNYHILLS ROAD OAKLAND CALIFORNIA 94610 |
International Classification(s)
Inventor(s)
Inventor Name | Address | # of filed Patents | Total Citations |
---|---|---|---|
Feinstein, Leonard G | Westborough, MA | 1 | 93 |
Kasem, Yehya M | Northboro, MA | 1 | 93 |
Nagy, Bela G | Acton, MA | 12 | 375 |
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

Renewals Detail

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 5139973 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!.