Ultraviolet laser system and method for forming vias in multi-layered targets
US5593606A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 18, 1994 |
| Grant date | Jan 14, 1997 |
| Priority date | — |
| Expiry date | Jul 18, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/108
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The output of a continuously pumped, Q-switched, Nd:YAG laser (10) is frequency converted to provide ultraviolet light (62) for forming vias (72, 74) in multi-layered targets (40). The parameters of the output pulses (62) are selected to facilitate substantially clean, simultaneous or sequential drilling or via formation in a wide variety of materials such as metals, organic dielectrics, and reinforcement materials having different thermal absorption characteristics in response to ultraviolet light. These parameters typically include at least two of the following criteria: high average power of greater than about 100 milliwatts measured over the beam spot area, a temporal pulse width shorter than about 100 nanoseconds, a spot diameter of less than about 50 microns, and a repetition rate of greater than about one kilohertz. The laser system (10) and method circumvent conventional depth of cut saturation limitations and can achieve an increased depth of cut per pulse in a target (40) formed of either single- or multi-layered material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.