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3D-Micromac AG, a developer of laser micromachining and roll-to-roll laser systems for the semiconductor, photovoltaic, medical device and electronics markets, today unveiled the microPRO™ RTP–its new laser annealing system designed to enable several key process steps in semiconductor, power device and MEMS manufacturing. Combining a state-of-the-art laser optic module with 3D-Micromac’s modular semiconductor wafer processing platform, the microPRO RTP provides selective annealing with high repeatability and throughput in a versatile system.

The microPRO RTP features a line scan option for vertical selective annealing and a step-and-repeat spot option for horizontal selective annealing, as well as three optional laser wavelengths (near infrared, green and ultraviolet). The microPRO RTP addresses a variety of applications, including:

  • Dopant activation for insulated gate bipolar transistors (IGBTs), as well as activation of backside illuminated (BSI) CMOS image sensors and amorphous silicon (a-Si) — the microPRO RTP uses a high-speed line scan with excellent energy homogeneity and repeatability to provide precise localization of the field stop layer, which minimizes heat transference to the front-side of the wafer
  • Ohmic contact formation in silicon carbide (SiC) power devices to improve resistance — using spot scanning with short laser pulses, microPRO RTP can process the entire metalized backside of SiC wafers, forming ohmic interfaces and curing grinding defects, while preventing the generation of large carbon clusters and heat-related damage to the front-side of the wafer
  • Giant magneto resistive (GMR) and tunneling magneto resistive (TMR) sensor manufacturing — using a selective step-and-repeat spot and variable laser energy, microPRO RTP can selectively heat functional areas on the sensor to form and orient the magnetic fields for these MEMS sensor types

“As microelectronics adopt 3D/stacked architectures to achieve more functionality, manufacturers need annealing solutions that can process the surface layers of their devices without affecting buried structures underneath. The migration to new materials and heterogeneous integration adds even more complexity to the annealing process, driving the need for selective exposure of functional areas, which only selective laser annealing can provide. Leveraging our years of experience in providing laser solutions to the semiconductor and microelectronics market, 3D-Micromac is pleased to offer our new microPRO RTP laser annealing solution, which provides the selectivity, flexibility and throughput our customers need to meet their unique annealing requirements,” stated Hans-Ulrich Zühlke, product manager at 3D-Micromac.

The microPRO RTP provides numerous advantages compared to existing annealing methods, including:
  • High precision and repeatability in both X and Y directions
  • High selectivity to different substrates and films, with multiple options for laser pulse length, energy and overlap to ensure no damage to the area surrounding the target site
  • Very high energy homogeneity
  • Precise process monitoring
  • Flexibility to handle substrate diameters ranging from 50mm up to 300mm

Media, analysts and potential customers interested in learning more about 3D-Micromac’s laser micromachining solutions, including the microPRO RTP, are invited to visit the company at SEMICON West 2018, July 10-12 at the Moscone Convention Center in San Francisco, Calif., in South Hall, booth #1645. More information on microPRO RTP is also available on https://3d-micromac.com/laser-micromachining/products/micropro/.

Cadence Design Systems, Inc. (NASDAQ: CDNS) today launched the Cadence Cloud portfolio, the first broad cloud portfolio for the development of electronic systems and semiconductors. The Cadence Cloud portfolio consists of Cadence-managed and customer-managed environments that enable electronic product developers to use the scalability of the cloud to securely manage the exponential increase in design complexity. With the new portfolio offerings, customers gain access to improved productivity, scalability, security and flexibility, through scalable compute resources available in minutes or hours instead of months or weeks, achieving better overall throughput in the development process.

The announcement was made at the 55th annual Design Automation Conference (DAC) being held in San Francisco at Moscone Center West, June 25-28, 2018. Cadence is located in booth 1308 in the main exhibit hall and booth 1245 in the Design Infrastructure Alley. For more information on the new Cadence Cloud portfolio, please visit www.cadence.com/go/cadencecloud.

Cadence gained extensive cloud experience by hosting design environments for more than 100 customers of varying sizes and architecting many of its products to be massively parallel for improved scalability in the cloud.

“The cloud will fundamentally influence silicon design by giving semiconductor companies the ability to optimize their capital versus operational expenses for computing infrastructure,” said Suk Lee, senior director Design Infrastructure Marketing Division at TSMC. “Cadence has passed our rigorous cloud security audits and is authorized to engage with mutual customers on the Cadence Cloud using TSMC process models and rule decks.”

“While many industries have previously adopted the cloud to address compute-intensive workloads, systems and semiconductor companies have faced unprecedented challenges that have made cloud adoption difficult until now,” said Richard Wawrzyniak, principal analyst for ASIC & SoC at Semico Research Corp. “Some of the challenges included security concerns and the sheer amount of design data and the inherent scalability limitations with electronic design automation tools. The Cadence approach to the cloud addresses historical industry issues, opening the door for customers to adopt the cloud and enter the next generation of chip design development.”

Leti, a research institute of CEA Tech, today announced that field trials of its new Low Power Wide Area (LPWA) technology, a waveform tailored for Internet of Things (IoT) applications, showed significant performance gains in coverage, data-rate flexibility and power consumption compared to leading LPWA technologies.

Leti’s LPWA approach includes its patented Turbo-FSK waveform, a flexible approach to the physical layer. It also relies on channel bonding, the ability to aggregate non-contiguous communication channels to increase coverage and data rates. The field trials confirmed the benefits of Leti’s LPWA approach in comparison to LoRaTM and NB-IoT, two leading LPWA technologies that enable wide-area communications at low cost and long battery life.

The results indicate the new technology is especially suitable for long-range massive machine-type communication (mMTC) systems. These systems, in which tens of billions of machine-type terminals communicate wirelessly, are expected to proliferate after 5G networks are deployed, beginning in 2020. Cellular systems designed for humans do not adequately transmit the very short data packets that define mMTC systems.

Figure 1: Performance chart comparison

Designed to demonstrate the performance and flexibility of the new waveform, the field-trial results stem primarily from the system’s flexible approach of the physical layer. The flexibility allows data-rate scaling from 3Mbit/s down to 4kbit/s, when transmission conditions are not particularly favorable and/or a long transmission range is required.

Under favorable transmission conditions, e.g. a shorter range and line of sight, the Leti system can select high data rates using widely deployed single-carrier frequency-division multiplexing (SC-FDM) physical layers to take advantage of the low power consumption of the transmission mode. Under more severe transmission conditions, the system switches to more resilient high-performance orthogonal frequency division multiplexing (OFDM). When both very long-range transmission and power efficiency are required, the system selects Turbo-FSK, which combines an orthogonal modulation with a parallel concatenation of convolutional codes and makes the waveform suitable to turbo processing. The selection is made automatically via a medium access control (MAC) approach optimized for IoT applications.

“Leti’s Turbo-FSK receiver performs close to the Shannon limit, which is the maximum rate that data can be transmitted over a given noisy channel without error, and is geared for low spectral efficiency,” said Vincent Berg, head of Leti’s Smart Object Communication Laboratory. “Moreover, the waveform exhibits a constant envelope, i.e. it has a peak-to-average-power ratio (PAPR) equal to 0dB, which is especially beneficial for power consumption. Turbo-FSK is therefore well adapted to future LPWA systems, especially in 5G cellular systems.”

In the new system, the MAC layer exploits the advantages of the different waveforms and is designed to self-adapt to context, i.e. the usage scenario and application. It optimally selects the most appropriate configuration according to the application requirements, such as device mobility, high data rate, energy efficiency or when the network becomes crowded, and is coupled with a decision module that adapts the communication depending on the radio environment. The optimization of the application transmission requirements is realized by the dynamic adaptation of the MAC protocol, and the decision module controls link quality.

Synopsys, Inc. (Nasdaq: SNPS) today announced that Samsung Electronics Co., Ltd. has certified the Synopsys Custom Design Platform for Samsung Foundry’s 7-nanometer (nm) Low Power Plus (LPP) process Samsung Foundry’s 7LPP is its first semiconductor process technology to use extreme ultraviolet (EUV) lithography, a process technology that greatly reduces complexity and offers significantly better yield and fast turnaround time when compared to its 10-nanometer (10nm) FinFET predecessors. Synopsys custom design tools have been updated to support Samsung Foundry’s 7LPP requirements. In addition, a Synopsys-ready process design kit (PDK) and custom design reference flow are available from Samsung Foundry.

The Synopsys Custom Design Platform has been certified for Samsung Foundry’s 7LPP process technology. The platform is centered around the Custom Compiler custom design and layout environment, and includes HSPICE, FineSim SPICE and CustomSim FastSPICE circuit simulation, StarRC parasitic extraction, and IC Validator physical verification. To support efficient 7LPP custom design, Synopsys and Samsung Foundry have collaborated to develop a reference flow that includes a set of tutorials illustrating key requirements of 7-nm design and layout. These tutorials include sample design data and step-by-step instructions for performing typical design and layout tasks. Topics covered include electrical rule checking, circuit simulation, mixed-signal simulation, Monte Carlo analysis, layout, parasitic analysis, and electromigration.

To achieve certification from Samsung Foundry, Synopsys tools have been optimized to support the demanding requirements of 7-nm design, including:

  • Accurate FinFET device modeling with device aging effect
  • Advanced Monte Carlo simulation features to enable efficient analysis
  • High-performance transient noise simulation for analog and RF designs
  • High-performance post-layout simulation to enable parasitic-aware design and simulation
  • Dynamic circuit ERC for device voltage checks
  • High-performance transistor-level EM/IR analysis to minimize over-design
  • Efficient symbolic editing of FinFET device arrays
  • EUV support
  • Coverage-based via resistance extraction

“Our custom design collaboration with Synopsys has expanded substantially over the past two years,” said Ryan Sanghyun Lee, vice president of Foundry Marketing Team at Samsung Electronics. “With this latest effort, we have added Synopsys Custom Design Platform support for our 7LPP process, including a custom design reference flow based on Synopsys tools.”

“We’ve been collaborating closely with Samsung Foundry to simplify custom design using FinFET process technology,” said Bijan Kiani, vice president of product marketing at Synopsys. “Together we have delivered certified tools, a reference flow, a PDK, simulation models, and runsets to enable Samsung customers to achieve robust custom designs on the 7LPP process.”

Virginia Commonwealth University researchers have discovered a novel strategy for creating superatoms — combinations of atoms that can mimic the properties of more than one group of elements of the periodic table. These superatoms could be used to create new materials, including more efficient batteries and better semiconductors; a core component of microchips, transistors and most computerized devices.

Batteries and semiconductors rely on the movement of charges from one group of atoms to another. During this process, electrons are transferred from donor atoms to acceptor atoms. Forming superatoms that can supply or accept multiple electrons while maintaining structural stability is a key requirement for creating better batteries or semiconductors, said Shiv Khanna, Ph.D., Commonwealth Professor and chair of the Department of Physics in the College of Humanities and Sciences. The ability of superatoms to effectively move charges while staying intact is attributed to how they mimic the properties of multiple groups of elements.

“We have devised a new approach in which one can synthesize such metal-based superatoms,” Khanna said.

In a paper published in Nature Communications last week, Khanna theoretically proved a method of building superatoms that could result in the creation of more effective energetic materials. The work was funded by the Air Force Office of Scientific Research.

“Semiconductors are used in every sphere of life,” Khanna said. “Superatoms that could substantially enhance electron donation would be a significant societal benefit.”

Currently, alkali atoms, which form the first column of the periodic table, are optimal for donating electrons. These naturally occurring atoms require a low amount of energy to donate an electron. However, donating more than one electron requires a prohibitively high amount of energy.

Khanna and colleagues Arthur Reber, associate professor of physics, and Vikas Chauhan, a postdoctoral fellow in the Department of Physics, have created a process by which clusters of atoms can donate or receive multiple electrons using low levels of energy.

“The possibility of having these building blocks that can accept multiple charges or donate multiple charges would eventually have wide-ranging applications in electronics,” Khanna said.

While such superatoms already have been made, there has never been a guiding theory for doing so effectively. Khanna and his colleagues theorize that organic ligands — molecules that bind metal atoms to protect and stabilize them — can improve the exchange of electrons without compromising energy levels.

They considered this theory using groups of aluminum clusters mixed with boron, carbon, silicon and phosphorous, paired with organic ligands. Using computational analysis, they demonstrated the cluster would use even less energy to donate an electron than francium, the strongest naturally occurring alkali electron donor.

“We could use ligands to take any cluster of atoms and turn it into either a donor or acceptor of electrons,” Khanna said. “We could form electron donors that are stronger than any element found on the periodic table.”

IBM’s announcement that they had produced the world’s smallest computer back in March raised a few eyebrows at the University of Michigan, home of the previous champion of tiny computing.

Now, the Michigan team has gone even smaller, with a device that measures just 0.3 mm to a side—dwarfed by a grain of rice.

The reason for the curiosity is that IBM’s claim calls for a re-examination of what constitutes a computer. Previous systems, including the 2x2x4mm Michigan Micro Mote, retain their programming and data even when they are not externally powered.

Unplug a desktop computer, and its program and data are still there when it boots itself up once the power is back. These new microdevices, from IBM and now Michigan, lose all prior programming and data as soon as they lose power.

“We are not sure if they should be called computers or not. It’s more of a matter of opinion whether they have the minimum functionality required,” said David Blaauw, a professor of electrical and computer engineering, who led the development of the new system together with Dennis Sylvester, also a professor of ECE, and Jamie Phillips, an Arthur F. Thurnau Professor and professor of ECE.

In addition to the RAM and photovoltaics, the new computing devices have processors and wireless transmitters and receivers. Because they are too small to have conventional radio antennae, they receive and transmit data with visible light. A base station provides light for power and programming, and it receives the data.

One of the big challenges in making a computer about 1/10th the size of IBM’s was how to run at very low power when the system packaging had to be transparent. The light from the base station—and from the device’s own transmission LED—can induce currents in its tiny circuits.

“We basically had to invent new ways of approaching circuit design that would be equally low power but could also tolerate light,” Blaauw said.

For example, that meant exchanging diodes, which can act like tiny solar cells, for switched capacitors.

Another challenge was achieving high accuracy while running on low power, which makes many of the usual electrical signals (like charge, current and voltage) noisier.

Designed as a precision temperature sensor, the new device converts temperatures into time intervals, defined with electronic pulses. The intervals are measured on-chip against a steady time interval sent by the base station and then converted into a temperature. As a result, the computer can report temperatures in minuscule regions—such as a cluster of cells—with an error of about 0.1 degrees Celsius.

The system is very flexible and could be reimagined for a variety of purposes, but the team chose precision temperature measurements because of a need in oncology. Their longstanding collaborator, Gary Luker, a professor of radiology and biomedical engineering, wants to answer questions about temperature in tumors.

Some studies suggest that tumors run hotter than normal tissue, but the data isn’t solid enough for confidence on the issue. Temperature may also help in evaluating cancer treatments.

“Since the temperature sensor is small and biocompatible, we can implant it into a mouse and cancer cells grow around it,” Luker said. “We are using this temperature sensor to investigate variations in temperature within a tumor versus normal tissue and if we can use changes in temperature to determine success or failure of therapy.”

Even as Luker’s experiments run, Blaauw, Sylvester and Phillips look forward to what purposes others will find for their latest microcomputing device.

“When we first made our millimeter system, we actually didn’t know exactly all the things it would be useful for. But once we published it, we started receiving dozens and dozens and dozens of inquiries,” Blaauw said.

And that device, the Michigan Micro Mote, may turn out to be the world’s smallest computer even still—depending on what the community decides are a computer’s minimum requirements.

What good is a tiny computer? Applications of the Michigan Micro Mote:

  • Pressure sensing inside the eye for glaucoma diagnosis
  • Cancer studies
  • Oil reservoir monitoring
  • Biochemical process monitoring
  • Surveillance: audio and visual
  • Tiny snail studies

The study was presented June 21 at the 2018 Symposia on VLSI Technology and Circuits. The paper is titled “A 0.04mm3 16nW Wireless and Batteryless Sensor System with Integrated Cortex-M0+ Processor and Optical Communication for Cellular Temperature Measurement.”

The work was done in collaboration with Mie Fujitsu Semiconductor Ltd. Japan and Fujitsu Electronics America Inc.

Researchers at Chalmers University of Technology, Sweden, have developed a graphene assembled film that has over 60 percent higher thermal conductivity than graphite film – despite the fact that graphite simply consists of many layers of graphene. The graphene film shows great potential as a novel heat spreading material for form-factor driven electronics and other high power-driven systems.

Until now, scientists in the graphene research community have assumed that graphene assembled film cannot have higher thermal conductivity than graphite film. Single layer graphene has a thermal conductivity between 3500 and 5000 W/mK. If you put two graphene layers together, then it theoretically becomes graphite, as graphene is only one layer of graphite.

Today, graphite films, which are practically useful for heat dissipation and spreading in mobile phones and other power devices, have a thermal conductivity of up to 1950 W/mK. Therefore, the graphene-assembled film should not have higher thermal conductivity than this.

Research scientists at Chalmers University of Technology have recently changed this situation. They discovered that the thermal conductivity of graphene assembled film can reach up to 3200 W/mK, which is over 60 percent higher than the best graphite films.

In the graphene film, phonons — quantum particles that describe thermal conductivity — can move faster in the graphene layers rather than interact between the layers, thereby leading to higher thermal conductivity. Credit: Chalmers University of Technology/Krantz Nanoart

Professor Johan Liu and his research team have done this through careful control of both grain size and the stacking orders of graphene layers. The high thermal conductivity is a result of large grain size, high flatness, and weak interlayer binding energy of the graphene layers. With these important features, phonons, whose movement and vibration determine the thermal performance, can move faster in the graphene layers rather than interact between the layers, thereby leading to higher thermal conductivity.

“This is indeed a great scientific break-through, and it can have a large impact on the transformation of the existing graphite film manufacturing industry”, says Johan Liu.

Furthermore, the researchers discovered that the graphene film has almost three times higher mechanical tensile strength than graphite film, reaching 70 MPa.

“With the advantages of ultra-high thermal conductivity, and thin, flexible, and robust structures, the developed graphene film shows great potential as a novel heat spreading material for thermal management of form-factor driven electronics and other high power-driven systems”, says Johan Liu.

As a consequence of never-ending miniaturisation and integration, the performance and reliability of modern electronic devices and many other high-power systems are greatly threatened by severe thermal dissipation issues.

“To address the problem, heat spreading materials must get better properties when it comes to thermal conductivity, thickness, flexibility and robustness, to match the complex and highly integrated nature of power systems”, says Johan Liu. “Commercially available thermal conductivity materials, like copper, aluminum, and artificial graphite film, will no longer meet and satisfy these demands.”

The IP of the high-quality manufacturing process for the graphene film belongs to SHT Smart High Tech AB, a spin-off company from Chalmers, which is going to focus on the commercialisation of the technology.

Microelectrodes can be used for direct measurement of electrical signals in the brain or heart. These applications require soft materials, however. With existing methods, attaching electrodes to such materials poses significant challenges. A team at the Technical University of Munich (TUM) has now succeeded in printing electrodes directly onto several soft substrates.

Researchers from TUM and Forschungszentrum Jülich have successfully teamed up to perform inkjet printing onto a gummy bear. This might initially sound like scientists at play – but it may in fact point the way forward to major changes in medical diagnostics. For one thing, it was not an image or logo that Prof. Bernhard Wolfrum’s team deposited on the chewy candy, but rather a microelectrode array. These components, comprised of a large number of electrodes, can detect voltage changes resulting from activity in neurons or muscle cells, for example.

Researchers from the Technical University of Munich (TUM) have succeeded in printing microelectrode arrays directly onto several soft substrates. Soft materials are better suited for devices that directly measure electrical signals from organs like the brain or heart. Credit: N. Adly / TUM

Second, gummy bears have a property that is important when using microelectrode arrays in living cells: they are soft. Microelectrode arrays have been around for a long time. In their original form, they consist of hard materials such as silicon. This results in several disadvantages when they come into contact with living cells. In the laboratory, their hardness affects the shape and organization of the cells, for example. And inside the body, the hard materials can trigger inflammation or the loss of organ functionalities.

Rapid prototyping with inkjet printers

When electrode arrays are placed on soft materials, these problems are avoided. This has sparked intensive research into these solutions. Until now, most initiatives have used traditional methods, which are time-consuming and require access to expensive specialized laboratories. “If you instead print the electrodes, you can produce a prototype relatively quickly and cheaply. The same applies if you need to rework it,” says Bernhard Wolfrum, Professor of Neuroelectronics at TUM. “Rapid prototyping of this kind enables us to work in entirely new ways.”

Wolfrum and his team work with a high-tech version of an inkjet printer. The electrodes themselves are printed with carbon-based ink. To prevent the sensors from picking up stray signals, a neutral protective layer is then added to the carbon paths.

Materials for various applications

The researchers tested the process on various substrates, including PDMS (polydimethylsiloxane) – a soft form of silicon – agarose – a substance commonly used in biology experiments – and finally various forms of gelatin, including a gummy bear that was first melted and then allowed to harden. Each of these materials has properties suitable for certain applications. For example, gelatin-coated implants can reduce unwanted reactions in living tissue.

Through experiments with cell cultures, the team was able to confirm that the sensors provide reliable measurements. With an average width of 30 micrometers, they also permit measurements on a single cell or just a few cells. This is difficult to achieve with established printing methods.

“The difficulty is in fine-tuning all of the components – both the technical set-up of the printer and the composition of the ink,” says Nouran Adly, the first author of the study. “In the case of PDMS, for example, we had to use a pre-treatment we developed just to get the ink to adhere to the surface.”

Wide range of potential applications

Printed microelectrode arrays on soft materials could be used in many different areas. They are suitable not only for rapid prototyping in research, but could also change the way patients are treated. “In the future, similar soft structures could be used to monitor nerve or heart functions in the body, for example, or even serve as a pacemaker,” says Prof. Wolfrum. At present he is working with his team to print more complex three-dimensional microelectrode arrays. They are also studying printable sensors that react selectively to chemical substances, and not only to voltage fluctuations.

Scientists of the Far Eastern Federal University (FEFU) in cooperation with colleagues from the Russian Academy of Sciences (RAS), Australian and Lithuanian Universities have improved the technique of ultrasensitive nonperturbing spectroscopic identification of molecular fingerprints.

A group of physicists experimentally confirmed that molecular fingerprints of toxic, explosive, polluting and other dangerous substances could be reliably detected and identified by surface-enhanced Raman spectroscopy (SERS) using black silicon (b-Si) substrate. The results of the work are published in the authoritative scientific journal Nanoscale.

The needle-shaped surface structure of black silicon where needles are made of single-crystal silicon. The nanomaterial is absolutely chemically inert, non-invasive, and could support a strong and non-distorted signal Credit: FEFU press office

“When detecting the smallest molecules using SERS spectroscopy their interaction with the nanostructured substrate – the platform allowing ultrasensitive identification – is crucial”, the head of research team Alexander Kuchmizhak, Ph.D., reported. Alexander is a researcher of the Department of Theoretical and Nuclear Physics of the School of Natural Sciences of the FEFU. He also added: “Currently noble metals-based substrates are chemically active and as a result, they distort the characteristic molecules signals.”

“Due to its’ special morphology black silicon significantly enhances the signal from the molecules wanted. This nanomaterial doesn’t support catalytic conversion of the analyte as it could be in the case of the metal-based substrates applying. The ‘black silicon’- based substrate is unique: being absolutely chemically inert and non-invasive it could support a strong and non-distorted signal,” told Alexander Kuchmizhak.

The substrate can be fabricated by using the easy-to-implement scalable technology of plasma etching, thus has good prospects for commercial implementation. Such inexpensive non-metallic substrates with high accuracy of detection can be promising for routine SERS applications, where the non-invasiveness is of high importance.

Valuable properties of black silicon were discovered thanks to extensive scientific cooperation. Samples of the material were developed and provided by Australian colleagues, experimental work was carried out in the laboratories of the Institute of Chemistry and the Institute of Automation and Control Processes of the Far Eastern Branch of the RAS, as well as in the Scientific and Educational Center “Nanotechnologies” of the Engineering School of the FEFU.

The way that electrons paired as composite particles or arranged in lines interact with each other within a semiconductor provides new design opportunities for electronics, according to recent findings in Nature Communications.

What this means for semiconductor components, such as those that send information throughout electronic devices, is not yet clear, but hydrostatic pressure can be used to tune the interaction so that electrons paired as composite particles switch between paired, or “superconductor-like,” and lined-up, or “nematic,” phases. Forcing these phases to interact also suggests that they can influence each other’s properties, like stability – opening up possibilities for manipulation in electronic devices and quantum computing.

Two different kinds of electron arrangements in a semiconductor, paired as composite particles or lined-up, can interact with and tweak each other in the presence of hydrostatic pressure. Credit: Purdue University image/Gábor Csáthy

“You can literally have hundreds of different phases of electrons organizing themselves in different ways in a semiconductor,” said Gábor Csáthy, Purdue professor of physics and astronomy. “We found that two in particular can actually talk to each other in the presence of hydrostatic pressure.”

Csáthy’s group discovered that hydrostatic pressure, which is 10,000 times stronger than ambient pressure, compresses the lattice of atoms in a semiconductor and, therefore, influences the electron arrangement within a two-dimensional electron gas hosted by the semiconductor. The strength of the pressure determines which arrangement is favored and tunes the transition between the paired and lined-up phases, making them more tailorable for an application. Of the two phases, the paired phase may support a certain type of quantum computing.

“We can also tune the interaction by engineering the semiconductor,” Csáthy said. “Say, for example, we grew a semiconductor with a particular width and electron density that we estimated could stabilize the nematic phase. Then we’ve tuned the electron-electron interaction as a result.”

Michael Manfra, Purdue professor of physics and astronomy, electrical and computer engineering and materials engineering, and researchers Loren Pfeiffer and Kenneth West at Princeton University grew the semiconductor samples for this study. Yuli Lyanda-Geller, Purdue associate professor of physics and astronomy, provided theoretical support for the understanding on how these electron-electron interactions took place.