APEX Showcases AP/SMT Synergy
By Françoise von Trapp, Associate Editor
There’s a lot of talk in the electronics industry about the blurred lines between advanced packaging (AP) and surface mount technology (SMT), and nowhere was that more apparent than on the trade show floor at the IPC Printed Circuits Expo, APEX, and the Designers Summit, held February 7-10, 2006, at the Anaheim Convention Center in Anaheim, CA.
While most exhibiting companies focused on showcasing their latest surface mount developments, many had products and services offering solutions that integrated packaging as well. For example, among the six new products introduced by ERSA, one was a fully automated inspection and rework machine that also provides solutions to increase yields in certain types of MEMS packages. Because boards with mounted MEMS sensors intended for use in automobile airbags can’t be handled manually, those found to have bridging defects must be discarded. This machine scans, detects, and repairs these boards automatically, reducing waste and increasing yield while eliminating manual handling.
Viscom exhibited an automated optical (AOI) wire bond inspection system. Wire bonding is an important packaging technique for high-density chip attachment. During inspection, high-resolution cameras register each solder joint and wire bond to detect defects in die bonds, ball-to-wedge, and wedge-to-wedge wire bonds. The extent of the inspection covers bond positions, leads, dice, and component positions.
X-Tek Systems demonstrated the latest software and hardware advances to its X-ray inspection system, including feature recognition into the nanometer range and a viewing angle of up to 75° for BGA, µBGA, multi-layer board, and PCB solder joint inspection, and analysis of BGA ball wetting, attachment, cracks and delaminations.
Crossing into the packaging side with the introduction of their interferometric bump inspection system (IBIS) still in prototype stages was Lloyd-Doyle, an optical test supplier in the PCB industry. Using parallel digital signal processing technology coupled with true white light interferometry, the IBIS inspects and reports on the position, height, and shape of solder bumps on the die-attach side of chip carriers ensuring that the carriers are within specification for chip attachment.
Dispense and underfill have become more important to packaging as smaller components and lead-free alloys lead to brittle fracture failure. Underfill in BGA and flip chip packages is commonplace, as is conformal coating application after packages are mounted on boards. Asymtek, designers and manufacturers of dispensing and conformal coating systems, introduced their new jetting technology that can jet-dispense fluids through holes in radio frequency (RF) shields to underfill the chips below. Underfilling chips after they are packaged under the shield saves production time and, since the boards can be reflowed concurrently, eliminates the second reflow step, which many lead-free solder formulations do not tolerate. For its part, Henkel Industries has come up with a fine-pitch solder paste designed to underfill chip scale packages (CSPs).
In the area of circuit board assembly, Hover-Davis demonstrated their new direct-die feeder capable of feeding bare die and flip chips with high throughput, and can be mounted on any placement machine. Vertical-orientation wafer placement accepts wafers up to 8". The feeder analyzes the wafers, picks only the good die, and feeds them to the placement module. The demonstration featured the feeder mounted on a Siemens machine, which combines processes and eliminates an entire line of production. Juki Automation Systems also displayed innovation in assembly. They exhibited a system capable of placing advanced packages such as SiPs, MCMs, and other mixed technology applications, as well as standard SMT.
The driving force around mixed technology is the expansion of applications requiring volume assembly of die below 1 mm sq, such as RFID and LED technologies, according Roland Heitmann, V.P. sales and marketing for Hover-Davis. “We believe these solutions have the capability of offering our customers unprecedented reductions in assembly cost, which in turn will aid in the proliferation of new products and technologies,” noted Heitmann.
Addressing the integration of back-end processes from an organizational perspective, Heraeus, a supplier of electronics materials, announced the merging of its bonding wire and SMT divisions, forming the Contact Materials Division (CMD). “The joining of the two divisions will create a new organization that has an understanding of the electronics industry, from component assembly to final packaging,” said Brian Bauer, business manager for surface mount materials at Heraeus.
With miniaturization, SiPs, chip-on-board assembly, etc., it seems more and more companies are focusing on solutions to integrate processes and carve out their niche in the market. At SEMICON West 2006, to be held July 10-14, 2006 at the Moscone Center in San Francisco, CA, it will be interesting to discover where the front- and back-end lines blur as well. This synergy can only lead to more streamlined operations, resulting in lowering costs, increasing throughput and higher yields. Not bad for a day’s work.