Product life cycles are getting shorter, putting more pressure on the price of products and components. One of these components is the PCB (Printed Circuit Boards). This component is specially designed and built for each new product. One of the most expensive steps in the fabrication of the PCB is drilling the holes for connecting the conductive layers the so called 'vias'. Besides reducing the cost of this step the industry needs smaller holes to connect the new component packages such as Ball Grid Arrays, Chip Scaled Packages and Flip-Chips. With current drill techniques it is not possible to meet the demand for small holes without paying high cost penalties.
Without a new and cost-effective technology for forming small holes the new packages which will come to the market cannot be connected which will slow down the development of smaller products.
The consortium has the objective to build a system which can manufacture small holes (hole diameter 50 um) at a low cost. This machine will use state of the art laser techniques and beam position systems to compete with other methods such as plasma and photo definable dielectrics. Recent studies showed that laser has many advantages over other techniques. There is no limitation on materials which can be laser drilled. Other hole forming processes are limited to only a few exotic materials. The hole diameter can be much smaller than the ones formed with a plasma or photo definable dielectric . The investment for a laser workstation is much smaller than for a plasma process.
It is planned that each partner in the project cover different disciplines to make this project a success. Baccini (I) will build the workstation with a high speed X and Y stage and a galvo beam positioning system to be able to compete with the systems built in USA and Japan. This workstation will be able to move the laser-beam to 150 different positions per second. The drill speed will be determined by the number of pulses needed to drill a particular material. If three pulses are needed to form the hole the drilling speed will be 50 holes a second. The French company SAT will supply the laser source. For hole formation a TEA (Transverse Excited Atmosphere) laser is chosen. This high throughput laser is very effective to drill PCB material, which consist mostly out of a epoxy resin and a glass reinforcement. Due to its short and sharp pulses it generates very little thermal energy resulting in high quality holes.
The third partner in the project and end-user is Mommers Print Service (NL). This company has been exploring the field of hole formation for years and has a lot of experience which it will put into the project. It is also responsible for the reliability and destructive testing of these so called Microvias.