Press: Oh-Two, Oh-What?

Oh-Two, Oh-What?

Hearing aids offer one home for teeny 0201 passives, but is more widespread usage near?

By Kelly Barrett -- 10/23/00

You probably can't see them, but someday, they may allow you to hear better. The newest-size passive component is the tiny 0201.

Hearing aids and other highly specialized miniature electronics are in the niche market already hungry for these almost-invisible specks. Devices built to this new level of downsizing are just 20 thousandths of an inch by 10 thousandths of an inch small. To get a visual on this, just look at the period at the end of this sentence. It covers the same area as an 0201 device.

KOA Speer Electronics, Inc., Santa Clara, Calif. has capacity for 50 million pieces of 0201 devices per month, according to Scott Brown, senior product manager. Target markets include hearing aids, pacemakers, voltage-controlled oscillators and multichip modules. Just when board assemblers are getting the knack of putting down 0402s (just 40 mils x 20 mils), the component industry is gearing up the next generation of devices that are 75 percent smaller. Opinions of parts makers, assembly gear vendors and others differ, however, on how much duty the miniscule 0201s will soon see in high-volume mainstream applications like cell phones, which are now heavily embracing 0402s. But designers of hearing aids and the like are already designing in the first 0201s.

"These 0201 parts serve a niche market, and with a significant cost premium over 0402s and 0603s, designers are using 0201s only if they have serious board-space limitations," said Scott Brown, senior product manager at component maker Koa Speer Electronics Inc., Bradford, Pa. Koa Speer serves markets that require specialized packaging for products including hearing aids, pacemakers, voltage-controlled oscillators (VCOs) and multichip modules, according to Brown, who is based in Santa Clara, Calif.

Koa Speer has been in production of 0201 resistors for two years, with current capacity of 50 million pieces per month, according to Brown. Due to handling and cost constraints, the volume of 0201s is unlikely to reach that of 0402s, he believes. The 0402s meet the size requirements of the primary application, cell phones, which can only shrink so much and still be practical for the user, Brown said.

"Initially, 0201 devices will be used in the smallest, highest-density circuit designs for products such as handhelds, implantable devices and hearing aids," said Jim Wright, director of the technical product marketing group, NIC Components Corp., Melville, N.Y. NIC is currently promoting 0201-size chip resistors and will soon offer 0201 ceramic chip capacitors, according to Wright.

Other passive manufacturers offering 0201s include RCD Components Inc., Philips, Thin Film Technology Corp., Vishay Intertechnology Inc., Murata Manufacturing Co. Ltd., and others.

While some see 0201s as a technology leap primarily aimed at highly specialized applications, others see them as the next logical step in the progression of shrinking electronics and expect heavy penetration of high-volume areas such as cell phones. One other alternative to decreasing the size of devices is to gang them together, but integrated passives haven't seen wide market acceptance yet, observers note.

"Miniaturization of cell phones, pagers and personal digital assistants has driven the size of passives down to 0603, 0402, and more recently, to 0201," said George Westby, director of the SMT laboratory at assembly equipment maker Universal Instruments Corp., Binghamton, N.Y. "With the combined pressures of weight, size and cost, 0201 passives are a natural part of the evolution of cell phones," Westby concluded.

Even though growing volumes of 0201s may be on the horizon, there's a long list of handling and assembly issues with devices that barely can be spied with the naked eye. "The task at hand is implementing this next-generation component into the existing surface-mount process without seeing the assembly quality suffer," said Jon Medernach, eastern regional sales representative, Panasonic Create Group, Westwood, Mass.

The process of adopting this new size may follow the process that 0402s saw when they were introduced. Japan seems to be leading the way with more than 30 users of the tiny device including VCOs and digital camcorders.

"Our factory in Tosu, Japan, is supporting customers assembling 0201s in volume manufacturing. In fact, one customer is placing six million a month," Medernach reported. The Japan plant is researching items ranging from optimizing how the devices are positioned on-tape to designing the best aperture size for the stencil used to screen solder paste onto the board, Medernach added.

"We are working to decrease the gap between components to more fully utilize the reduced component size. Most equipment manufacturers are currently capable of placing 0201s at 200-micron spacings; by reducing that spacing to 150 microns, the density increases by nearly 20 percent," Medernach said. Panasonic's goal is 100-micron spacing and a 10 part-per-million defect rate.

One type of common defect is known as tombstoning, a haunting little trick the device plays when it pops up on-end during the solder reflow process, thus resembling a tombstone. Reworking this defect is no treat, as any technician knows.

Assemblers aren't the only ones facing the daunting 0201-implementation task. "Challenges to MLCC (multilayer ceramic chip capacitors) producers include achieving a useful capacitance value at a reasonable price in such a small size. The ability to produce thinner dielectric layers with corresponding lower voltage ratings is needed to achieve effective capacitance values in 0201 sizes," NIC's Wright explained.

"We use unique manufacturing, handling and taping methods for the 0201-size chips," said Koa Speer's Brown. "Both the manufacturers and the assemblers face handling challenges due to the small physical size," he added.

Koa Speer has capacity for 50 million pieces of 0201 devices per month, according to Scott Brown, senior product manager. Target markets include hearing aids, pacemakers, VCOs and multichip modules.

Equipment manufacturers are developing optimized processes to assemble 0201 devices in high-volume production. Medernach of Panasonic Create Group hopes to implement 0201s into existing surface-mount processes without any degradation in quality.

"With the combined pressures of weight, size and cost, 0201 passives are a natural part of the evolution of cell phones," said Westby. However, the newest size devices don't come without a host of handling and assembly challenges.