Manufacturing Bits: March 8

5G mmWave consortium; roll-to-roll measurements; nano-thermometers.


5G mmWave consortium
Amid a slowdown in the cell phone business, the market is heating up for perhaps the next big thing in wireless—5th generation mobile networks or 5G. Carriers, chipmakers and telecom equipment vendors are all rushing to get a piece of the action in 5G, which is the follow-on to the current wireless standard known as 4G or long-term evolution (LTE).

Radio-frequency (RF) technology is a critical part of the wireless infrastructure. Today’s 4G networks operate from 700 MHz to 3.5 GHz. In contrast, 5G schemes will need to operate at the unlicensed or millimeter-wave frequency bands, which provide 10 times more bandwidth than 4G networks. 5G may operate anywhere from 6 to 60 GHz, or higher.

The problem? At times, millimeter-wave chips consume too much power.

In response, a group has formed a new consortium to address the power consumption problems. The consortium, dubbed INSIGHT or the Integration of III-V Nanowire Semiconductors for Next Generation High Performance CMOS SOC Technologies, plans to develop III-V CMOS technology for 5G networks. The goal is to develop a production-worth III-V CMOS technology on silicon substrates.

The consortium includes Fraunhofer IAF, CEA-Leti, Lund University, University of Glasgow, Tyndall National Institute and IBM. Lund University is coordinating this new European Horizon 2020 research project. The project has been funded with 4.3 million Euros over 36 months.

“The fabrication of high-performance III-V components on large Si substrates using CMOS compatible technologies opens a path for cost reduction of millimeter-wave key components with minimized usage of critical materials” said Lars-Erik Wernersson, a professor at Lund University and coordinator for INSIGHT, on the university’s Web site.

Roll-to-roll measurements
The National Institute of Standards and Technology (NIST) has devised a technique to conduct on-the-fly measurements in roll-to-roll manufacturing applications.

Today, there are several applications in roll-to-roll manufacturing. For example, using a roll-to-roll process, graphene and carbon nanotubes can be used to make various next-generation flexible and wearable electronics.

The problem? There are few ways to conduct measurements in these types of systems.

In response, NIST has developed a permittivity analysis meter (PAM). The PAM is a non-contact microwave method for measuring the dielectric constant and conductivity properties in materials. It can conduct measurements in a matter of milliseconds.

The measurements are taken using a metal boxy known as a microwave cavity. Electromagnetic waves are built up in the cavity. This is done at a specific resonance frequency, depending on the box’s size and shape. In the process, an object is placed inside the cavity. The resonance frequency changes, depending on the object’s size, electrical resistance and dielectric constant.

An electrical circuit is used to measure the changes. The new method can measure materials on the whole roll or parts of the roll. “This method could significantly boost prospects of not making a faulty batch in the first place,” said Christian Long of NIST, on the agency’s Web site.

Roll-to-roll measurements (NIST)

Roll-to-roll measurements(NIST)

IBM and ETH Zurich have invented a technique to measure the temperature of tiny objects–scanning probe thermometry.

Researchers have basically developed a nano-thermometer. Measuring temperature at the nano-scale is important, but this technology presents a number of challenges, according to IBM and ETH Zurich.

In response, researchers have developed a single scan non-equilibrium contact thermometry technique. It measures the temperature using a scanning probe.

Researchers also eliminated the tip–sample contact-related artifact in its technology. In the nano-thermometer from IBM and ETH Zurich, two signals are measured simultaneously. The first signal is a small heat flux. The second measures a resistance to heat flow. The signals are then quantified to present a result.

“The technique is analogous to touching a hot plate and inferring its temperature from sensing the heat flux between our own body and the heat source,” said IBM scientist Bernd Gotsmann and co-inventor of the technology, on IBM Research’s Web site. “Essentially, the tip of the probe is our the hand. Our perception to hot and cold can be very helpful to get an idea of an objects temperature, but it can also be misleading if the resistance to heat flow is unknown.”

Fabian Menges, an IBM postdoc and co-inventor of the technique, added: “Not only is the scanning probe thermometer accurate, it meets the trifecta for tools: it’s easy to operate, simple to build, and very versatile, in that it can be used to measure the temperature of nano- and micro-sized hot spots that can locally effect the physical properties of materials or govern chemical reactions in devices such as transistors, memory cells, thermoelectric energy converters or plasmonic structures. The applications are endless.”