Unimicron Germany Rises from the Ashes with New Smart Factory


Reading time ( words)

The pre-treatment lines fed panels into the yellow safelight cleanroom area. Patterning was achieved using dry film photoresist and LED direct exposure, carried out in HEPA-filtered laminar-flow Class-1000 enclosures. Because the image information was all digital, set-up was instantaneous, and any job could be imaged on any machine, with a registration tolerance of ± 15 microns or better. Total imaging time per panel-side, including handling and registration, was less than 15 seconds, and the panel was flipped within the machine for second-side exposure.

uni6.jpg

Figure 6: Safelight imaging area.

The develop-etch-strip lines were equipped with digital pressure sensors and flow meters, enabling the ultimate in accurate setting and monitoring of process parameters for consistency and reproducibility. Etching technology had been developed to the highest level, with copper thickness, copper line profile and surface roughness measured continuously over the whole width of the panel. These parameters were particularly relevant in automotive medium- and long-range radar applications. At the upper end of the thickness scale, it was possible to etch 400-micron copper at a line speed of 1.6 metres per minute. At the lower end, for applications such as modified semi-additive technology, it was more cost-effective to produce 5-micron copper by differential etching down from 12 microns than to buy it in as ultra-thin copper-clad. A cupric chloride etchant was used, on a closed loop recycling system with copper recovery, and all the process chemistry was managed on lean principles with the minimisation of waste and a high level of environmental responsibility.

uni7.jpg

Figure 7: Develop-etch-strip lines.

uni8.jpg

Figure 8: Differential etching line.

uni9.jpg

Figure 9: Robot AGV takes etched panels for inspection.

After automated optical inspection, verification and, where necessary, automated optical repair, the etched innerlayer panels proceeded through surface preparation and bonding treatment to the lay-up area, where there was the option of pinned or pin-less tooling. The pin-less optical registration system had been refined and optimised in cooperation with the equipment supplier to achieve a layer-to-layer registration accuracy of ± 5 microns, and a proprietary self-learning software solution enabled the accuracy to be continuously measured and refined for any particular design.

Share

Print


Suggested Items

RTW IPC APEX EXPO 2019: LPKF Highlights Laser Processing Tech, Glass Drilling Capabilities

02/11/2019 | Real Time with...IPC
Guest Editor Joe Fjelstad sits down with Stephan H. Schmidt, LPKF president, who provides an overview of the company's laser processing machine and their capabilities, and highlights the new glass drilling capabilities.

Laser Focus on Flex and Rigid-flex

01/28/2019 | Barry Matties, I-Connect007
ESI’s Chris Ryder, director of Product Management, and Shane Noel, Flex Systems product manager, discuss laser vias for flex users and the increasing necessity for companies to collaborate early on and become more and more involved, whether that be in the product design, or with the process or base material manufacturers.

ESI’s Chris Ryder: There’s More to Choosing a Laser Than You Think

01/16/2019 | Barry Matties, I-Connect007
At the recent HKPCA show, I sat down with ESI’s Chris Ryder, director of product management—HDI—to discuss considerations for choosing a new laser system, and how ESI uses its decades of flex and rigid-flex drilling experience to help guide customers in their decision-making process.



Copyright © 2019 I-Connect007. All rights reserved.