- June 30, 2005, Nsenga Byrd Thompson, Associate Editor
Whether it’s the issue of ROI, getting a handle on the still-evolving EPCglobal standards, or trying to understand the mandates from Wal-Mart, Target, and the Dept. of Defense (DOD), there are a variety of concepts for converters to grasp in the busy new world of radio frequency identification (RFID).
In an effort to bring all the burning questions together, PFFC is presenting a three-part series to address many of the questions and concerns regarding implementation of RFID. In Part One of this "RFID Primer," we discuss the most basic component of them all—the anatomy of an RFID label.
Making the Label
Okay, you’re interested in making an RFID label, but you’re not sure if it’s right for your operation. Here’s the skinny on the little radio frequency labels everyone’s talking about.
RFID chips are manufactured and distributed as semi-conductive silicone wafers. These wafers are supplied to the inlay manufacturer (some inlay suppliers design and produce these wafers as well) where they may undergo additional processing to meet the inlay manufacturer’s engineering specifications.
The wafers are placed on a machine that will attach the integrated circuits (ICs) to an antenna. This "pick & place" procedure, which completes the inlay—the heart of the RFID label—is done using robotics in a clean room environment. Once the inlay is prepared, the label converter creates a "sandwich," placing the inlay inside a label substrate to create the completed RFID label.
Each chip is built with a memory bank that usually is left empty until the chip is built into the inlay and placed in the label substrate. The information then can be programmed into the chip by the label converter or by the end-user company.
Due to the need for a clean room environment for "pick & place" production, assembly of the inlay can be a difficult application for label converters to undertake, especially if they are concerned about stepping into a costly endeavor. However, there are opportunities for converters without a clean room to produce printed antennas for the inlays. In those applications, a strap product, which is basically two connector pads embedded with an RFID chip, can be supplied to the converter and assembled in an in-line printing process of the antenna. Industry experts agree this is still an emerging technology.
Antennas are designed and created using either copper etching or conductive ink technology. Major suppliers of RFID inlays have trademarked antenna designs that help increase performance and alleviate reading issues associated with problematic products such as metal and liquids. There is speculation that conductive inks for antenna, and eventually chip, printing will play a major role in driving label costs down, but there is growing sentiment this impact is still a few years down the road.
The idealistic $.05 label is said to have been a vision of the MIT Auto ID Center for item level tagging. For the generation of RFID labels being implemented now, mostly for the "slap & ship" supply chain management applications driven by mandates from Wal-Mart and the DOD, price points of RFID labels average between $.35 to $.45 and are as low as $.25. Special thanks to Anthony Sabetti of Texas Instruments for lending his expertise to the development of this article.
Quick Guide to RFID Suppliers
Whether you are ready to jump into the ever-growing world of RFID or just want more information, here’s a quick reference to some of the industry’s top inlay suppliers.