Dam bar cutting apparatus and dam bar cutting method
US5662822A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 1996 |
| Grant date | Sep 2, 1997 |
| Priority date | — |
| Expiry date | May 14, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2224/48091
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The array condition of leads (3) is detected by a photoelectric detector (41), the detection signal is subjected to signal processing to determine the timing to oscillate a pulsed laser beam, and a laser beam axis (13C) is relatively moved at a speed (v.sub.0) with a work table (21) while oscillating a pulsed laser beam (13A), thereby cutting a dam bar (5). At this time, the longitudinal size of a spot (13B) of the pulsed laser beam (13A) is adjusted to be twice or more the width of the dam bar (5) by a longitudinal beam transformer (11a), the transverse size of the spot 13B is adjusted to be not less than 1/2 but not more than 4/5 of the length of the dam bar (5) by a transverse beam transformer (11b), and a beam rotator (11c) is appropriately operated to make the longitudinal direction of the spot (13B) substantially aligned with the longitudinal direction of the lead (3) so that the spot (13B) lies across the width (W.sub.1) of the dam bar (5). As a result, the configuration after cutting the dam bar (5) becomes highly accurate and satisfactory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.