Semiconductor Maker Cuts Production Time with RTLS

Multibillion dollar semiconductor manufacturer Freescale Semiconductor is using RTLS technology to track wafers through the fabrication process. The system from AeroScout has been installed at one facility in Texas and reportedly saves several minutes at multiple steps in the production process.
Published: August 29, 2007

This article was originally published by RFID Update.

August 29, 2007—Freescale Semiconductor has slashed the time it takes to track work in process (WIP) and improved its manufacturing output by using RTLS technology to track wafers during production. Freescale, a $6.4 billion provider of various semiconductor products to the automotive and other industries, has been using RTLS for about six months at a facility in Austin, Texas, to track specialized containers, called lots, that carry wafers through the fabrication process.

“It used to take an average of about five minutes to find a lot after each process. Now it’s in the low numbers of minutes, and sometimes takes less than a minute,” Josh Slobin told RFID Update. Slobin is director of marketing at AeroScout, which provided the WiFi-based RTLS system to Freescale Semiconductor.

AeroScout’s RTLS tags, exciters, and software, plus additional wireless LAN access points (APs), were integrated with Freescale Semiconductor’s legacy wireless LAN and manufacturing control system. When workers complete a step in the production process, they put the lot aside, record the activity in the production system, and are directed to pick up the next lot for assembly. Before the RTLS system was installed, workers had to find lots manually and compare the ID number on the lot to the instruction they received from the software system. These processes created opportunities for misidentification and other errors, and required time-consuming manual searches.

Now each lot box is tracked with an RTLS tag. Workers are instructed to pick up specific lots and are directed to their location. The AeroScout exciter causes the RTLS tag to flash, making it even easier for workers to locate the lot.

Freescale Semiconductor has calculated the return on investment and has precise figures on how much throughput has improved since the RTLS system was implemented, but is not sharing details, according to Slobin. He said the system has been running for about six months and involves thousands of tags.

“AeroScout delivered an easy-to-use solution that helped us improve productivity, while leveraging our existing network infrastructure,” Chris Magnella, operations manager of the Freescale Semiconductor facility, is quoted in AeroScout’s announcement.

Most legacy wireless LANs that are adapted for RTLS applications require additional access points to provide the RF coverage necessary to perform accurate location calculations. Freescale Semiconductor did not have to significantly upgrade its WiFi wireless LAN, according to Slobin. “I’m told it was a small number of additional access points. It was not a doubling or tripling of their APs,” he said.

Many wafer fabrication facilities have wireless LANs, and the proven ability of WiFi-based RTLS systems to work with these systems and meet the requirements for use in clean room environments is making the technology popular with manufacturers, Slobin said.

“Freescale Semiconductor is one of the first semiconductor manufacturers to use RTLS, and they are doing some exciting things,” said Slobin. “However this is not an isolated case by any means. Semiconductor is becoming a hot industry for us.”

Analysts have been documenting and predicting strong growth for WiFi-based and other RTLS systems, but semiconductor manufacturing is not usually cited as a major market. Last month ABI Research noted WiFi RTLS is growing beyond its typical uses and industries (see Analyst on the Growing Market for WiFi-based RTLS).

Work-in-process tracking and other closed-loop RFID applications are also cited as growth areas. Last week Italian textile producer Griva announced its passive RFID application for WIP tracking yielded a 30 percent return-on-investment in only nine months (see Textile Manufacturer Gets Quick 30% ROI from RFID).