NEPCON West - Fiberoptic Expo Conference Proceedings


Author: Thomas Cinque et al.
Company: MIDAS Vision Systems
Date Published: 12/3/2002   Conference: NEPCON West - Fiberoptic Expo

Abstract: The information age has arrived. A growing percentage of the Earth’s population now has access to pagers, cellular phones, computers, personal digital assistants (PDA’s), and a host of other electronic devices. We can now instantly communicate around the globe with a device that fits into the palm of the hand. To meet these demands, packaging designers are shrinking design rules for substrate interconnects to assist in reducing overall package size.

These developments are made possible through advances in HDI (High Density Interconnect) circuit technology - the key attributes of HDI being packaging adaptability, circuit density, and more functionality on less real estate. Portable electronic manufacturers have a development roadmap to reduce the size for lines and spaces of the conductor traces below 50 µm. Many flexible circuit designs already contain areas with 50 µm lines and spaces, and designs with less than 30 µm are currently underway.

The demand for increased packaging density has intensified pressure on process, production, and quality control personnel to ensure that substrates can be produced in a timely manner with acceptable yields. Electrical testing can detect opens and shorts in the package, but cannot detect the more subtle defects that might result in field failures. Visual inspection in every step of the process is virtually impossible and unreliable given the small lines and spaces that will challenge a 100% inspection of the circuit. Neither of these traditional inspection methods produces the process feedback needed to improve the manufacturing process.

Automated Optical Inspection (AOI) is a necessary production yield management tool and provides important process feedback. However, traditional AOI technology cannot accurately inspect the fine features being manufactured in the HDI arena. This paper will discuss a method for implementing AOI into HDI manufacturing and how it serves as an enabling technology by providing reliable, consistent 100% inspection. Furthermore, this paper will illustrate how proper implementation and integration of AOI can provide real-time process feedback and the resultant yield increases that accrue.

Key words: automated optical inspection, AOI, high density interconnect, HDI, process monitoring, yield management.

Members download articles for free:

Not a member yet?

What else do you get when you join SMTA? Read about all of the benefits that go along with membership.

Notice: Sharing of articles is restricted to just your immediate work group. Downloaded papers should not be stored on an external network or shared on the internet.


SMTA Headquarters
6600 City West Parkway, Suite 300
Eden Prairie, MN 55344 USA

Phone +1 952.920.7682
Fax +1 952.926.1819