State-of-the-Art Technology Flashes
Updates in silicon and electronics technology.
Ed.: This is a special feature courtesy of Binghamton University.
IMEC and Intel researchers develop spintronic logic device. Spintronics is a budding path in the quest for a future beyond CMOS. Devices use much less power than their CMOS counterparts and keep their data unpowered. IMEC and Intel researchers have created a spintronic logic device that can be fully controlled with electric current rather than magnetic fields. An electron’s spin generates a magnetic moment, and when many electrons with identical spins are close together, their magnetic moments can align and join forces to form a larger magnetic field. Such a region is called a magnetic domain, and the boundaries between domains are called domain walls. A material can consist of many such domains and domain walls, assembled like a magnetized mosaic. (IEEC file #12091, Semiconductor Digest, 1/21/21)

Plasmonics: A new way to link processors with light. Plasmonic transceivers transfer large amounts of data between processors. Fiberoptic links are the main method of slinging data between computers in data centers. Silicon photonics components are large in comparison to their electronic counterparts because optical wavelengths are much larger than transistors and copper interconnects. University of Toronto and Arm researchers have developed new silicon transceiver components that rely on plasmonics instead of photonics. The results have transceivers capable of at least double the bandwidth, while consuming 33% of the energy and 20% of the area, and could be built atop the processor. (IEEC file #12097, IEEE Spectrum, 1/21/21)

Plasmonic transceiver
Possibilities for new transparent materials that conduct electricity. University of Minnesota researchers have made a discovery that provides the best qualities for touchscreens and smart windows: transparency and conductivity. The researchers are first to observe metallic lines in a perovskite crystal. The finding was made using advanced transmission electron micro-scopy (TEM), a technique that can form images with magnifications of up to 10 million. The conductive nature and preferential direction of these metallic line defects mean they can make a material that is transparent like glass and at the same time be directionally conductive like a metal. (IEEC file #12095, Printed Electronics World, 1/26/21)

Researchers create novel photonic chip. George Washington University researchers have developed a photonic digital-to-analog converter without leaving the optical domain. These converters can advance next-generation data processing hardware with high usage for data centers, 6G networks, and artificial intelligence. Current optical networks require a digital-to-analog conversion, which links digital systems synergistically to analog components. Using a silicon photonic chip platform, the researchers developed a digital-to-analog converter that does not require the signal to be converted in the electrical domain. This leads to high data-processing capabilities of optical data, interfacing to digital systems, and performing in a compact footprint. (IEEC file #12099, Science Daily, 2/2/21)

Passive thermal diode restricts direction of heat flow. Virginia Tech researchers have developed a thermal diode for aircraft thermal management technology that is adaptable to other areas, including electronic component and package cooling. Their approach uses two parallel copper plates separated by an insulating gasket micrometers thick; one plate contains a superhydrophilic wick structure, while the other is smooth and hydrophobic. The surface of the first plate has a wick-like structure consisting of micropillars that hold and conduct water, while the second parallel plate is smooth and coated with a hydrophobic water-repelling layer. (IEEC file #12100, Electronic Design, 1/26/21)

Passive thermal diode
Breakthrough in quantum photonics promises a new era in optical circuits. University of Southern California researchers have demonstrated that single photons can be emitted in a uniform way from quantum dots arranged in a precise pattern. The team used this to create single-quantum dots with their remarkable single-photon emission characteristics. To create the precise layout of quantum dots for the circuits, the team used a method called SESRE (substrate-encoded size-reducing epitaxy). The team fabricated regular arrays of nanometer-sized mesas with a defined edge orientation, shape on a flat semiconductor substrate (GaAs), with quantum dots created on top of the mesas. The ability to precisely align uniformly emitting quantum dots will enable the production of optical circuits with advancements in quantum computing and communications. (IEEC file #12113, Science Daily, 2/5/21)

Graphene “Nano-Origami” creates tiniest microchips yet. University of Sussex researchers have developed microchips made from graphene and other 2-D materials, using a form of “nano-origami.” By creating kinks in the structure of graphene, the nanomaterial behaves like a transistor, which is around 100 times smaller than conventional microchips. Using these nanomaterials will make computer chips smaller and faster. Ultimately, this will make computers and phones thousands of times faster. This technology, called “straintronics,” using nanomaterials as opposed to electronics, permits space for more chips inside any device. (IEEC file #12135, Printed Electronics World, 2/17/21)

LED can be integrated directly into computer chips. MIT researchers have fabricated a silicon chip with fully integrated LEDs bright enough to enable state-of-the-art sensor and communication technologies. The advance could lead to not only streamlined manufacturing, but also better performance for nanoscale electronics. In addition to cheaper manufacturing, the advance could also improve LED performance and efficiency as electronics shrink to ever smaller scales. At microscopic scale, III-V semiconductors have nonideal surfaces, riddled with “dangling bonds” that permit energy to be lost as heat rather than as light. In contrast, silicon forms a cleaner crystal surface. (IEEC file #12112, NASA Tech Briefs, 2/4/21)

LED integrated directly into computer chip
Reconfigurable electronics based on multiferroics and nanomagnetism. Virginia Polytechnic Institute researchers are developing new materials with large magnetoelectric (ME) coupling for next-generation multifunctional devices, including multi-state (neuromorphic-like) circuits, and E-field tunable microwave resonators for secure communications. Combining polarization and magnetization in the same solid controls the fundamental nature of electromagnetism in matter. Their research focuses on achieving the disruptive potential of emerging multifunctional magnetoelectrics, and in so doing lays the foundations for their use as a materials platform that would benefit future applications. (IEEC file #12133, Aerospace & Defense, 2/1/21)

Capturing free-space optical light for high-speed Wi-Fi. Visible and infrared light can carry more data than radio waves but has always been confined to a fiberoptic cable. Duke University researchers have made a major advance toward eliminating the fiber in fiberoptics. While working to create a free-space optical communication system for high-speed wireless internet, they showed speed and efficiency properties previously demonstrated on tiny plasmonic antennas can also be achieved on larger, centimeter-scale devices. The design uses silver nanocubes 60nm wide, spaced 200nm apart, covering 17% of the device’s surface. These nanocubes sit above a thin layer of silver, spaced by a coating of polymer with four layers of fluorescent dye. The nanocubes enhance the photonic capabilities of the fluorescent dye, causing a 910-fold increase in the overall fluorescence and a 133-fold emission rate enhancement. (IEEC file #12121, Science Daily, 2/11/22)

Experimental fiber optic cable insides
Market Trends
Optical sensor market is projected to reach $30 billion by 2026. The global optical sensor market is estimated to exceed $30 billion by 2026. The flourishing consumer electronics industry in developing countries is expected to boost optical sensor demand in the forthcoming years. The appliance and consumer electronics industry in India was valued at $10.9 billion in 2019 and is estimated to reach nearly $21.1 billion by 2025. Optical sensors are broadly utilized in consumer electronic devices for the detection of events, changes or input signals, and pass the information to other components. Increasing adoption of optical sensor for biometric recognition, high-speed detection, device authentication, and other security application in consumer electronic systems such as laptops, wearable electronics and smartphones will augment industry expansion. (IEEC file #12104, Semiconductor Digest, 1/22/21)

New electric car battery can charge in five minutes. A new electric car battery that can be fully charged in five minutes has been manufactured for the first time on a normal production line in China, based on designs by Israeli company StoreDot. The breakthrough could address a significant concern for electric car drivers: the fear of running out of power during a journey. The batteries are designed differently to standard Li-ion, replacing the graphite with semiconductor nanoparticles based on germanium. This battery design could have a significant impact on the adoption of electric vehicles, which are facing a bottleneck in countries such as the UK that have limited numbers of charging stations. (IEEC file #1210, Sky News, 1/19/21)

Hyundai EV includes optional rooftop solar panel. The most intriguing exterior feature on the new Hyundai Ioniq 5 fully electric, mid-size CUV (crossover SUV) is found on its roof: solar panels. You won’t be able to rely on the sun to fully recharge the 58kWh standard range or 72.6kWh long-range battery inside the Ioniq 5, with it acting as a complementary charging source that can help extend range. Hyundai says the solar panels can add up to 2,000km per year. (IEEC file #12146, ASME, 2/24/21)

Birds eye view of Hyundai EV
General Motors plans to phase out gas, diesel cars by 2035. General Motors plans to be carbon-neutral by 2040 and phase out gasoline and diesel cars by 2035. GM said by mid-decade it would offer 30 all-electric models, and by the end of 2025 40% of the company’s models will be battery electric vehicles. The company said it is investing $27 billion in electric and autonomous vehicles in the next five years. President Biden said he planned to replace the government’s fleet of cars and trucks with electric vehicles assembled in the US and signed several executive orders to address climate change, including establishing climate change as a national security priority. (IEEC file #12107, The Street, 1/28/21)

What to expect in 2021 from the MEMS industry. MEMS has brought a sensing revolution to consumer markets. MEMS microphones in every smartphone and tablet, together with CMOS image sensors, allow people to see and hear each other everywhere in the world. Global MEMS sensor revenue was $11.5 billion in 2019, and is set to reach $17.7 billion in 2025, at a 7.4% CAGR over this period. The market continues to be driven in 2021 with various trends and applications increasingly gaining momentum. For instance, MEMS-based environmental hubs and gas sensors are becoming ever more sought after, since people’s perceptions of their immediate environment has changed. The population cares more about the air they breathe, both inside houses but also outside due to pollution. (IEEC file #12129, Fierce Sensors, 2/10/21)

Surround sound from lightweight roll-to-roll printed loudspeaker paper. Chemnitz University of Technology researchers have developed loudspeakers as thin as paper with impressive sound. Previously the sonorous paper loudspeakers were manufactured in a semiautomatic single-sheet production process. In this process, ordinary paper or foils are printed with two layers of a conductive organic polymer as electrodes. A piezoelectric layer is sandwiched between them as the active element, which causes the paper to vibrate. Since this was only possible in individual sheets in limited formats, the efficiency of this manufacturing process is very low. Their latest project, roll-to-roll printed speaker paper using inline process monitoring, converts sheet production into roll production. (IEEC file #12125, Printed Electronics World, 2/4/21)

Girl standing under lightweight roll-to-roll printed loudspeaker paper
Recent Patents
Metal additive structures on printed circuit boards (assignee: Microsoft Tech.) pub. no. US10881037. PCBs include conductive metallic paths, such as vias, traces and pads. One or more metal additive structures are additively manufactured onto the PCBs in a manner that forms a continuous weld with at least one of the conductive metallic paths. As a result, the metal additive structures are continuous with the printed circuit board and do not require separate attachment mechanisms (e.g., soldering or mechanical fastening). The metal additive structures may include shield cans, frames, antennas or heatsinks for the printed circuit board.

Cooling system for a data center (assignee: Beijing Baidu Netcom Science & Tech.) pub. no. US10888033. A cooling system for a data center includes at least one liquid-cooling heat exchanger disposed above each of the integrated circuit boards to dissipate heat from a first heat source disposed on the integrated circuit board through an internal circulation coolant in the liquid-cooling heat exchanger; a liquid-cooling distributing device comprising a first pipeline in communication with the liquid-cooling heat exchanger; a second pipeline in communication with a first cooling tower; a heat exchanger configured to cool the internal circulation coolant from the liquid-cooling heat exchanger to a first temperature through an external circulation coolant from the first cooling tower; and the first cooling tower configured to cool the external circulation coolant supplied via the second pipeline to the second temperature.

Semiconductor package including stacked semiconductor chips (assignee: SK Hynix Inc.) patent no. 16/709786. Disclosed is a semiconductor package. The semiconductor package includes a substrate including an opening, a first semiconductor chip, disposed on the substrate, including a plurality of first chip pads exposed through the opening; a second semiconductor chip, disposed on the first semiconductor chip to partially overlap with the first semiconductor chip, including a plurality of second chip pads, aligned with the opening; and a redistribution layer formed on a surface on which the second chip pads of the second semiconductor chip are disposed. One or more of the second chip pads overlaps the first semiconductor chip and is covered by the first semiconductor chip, with the remaining pads of the second chip pads exposed through the opening.

Double-sided cooled molded semiconductor package (assignee: Infineon Technologies) patent no. 16/924851. A method of producing a molded semiconductor package includes attaching a first load terminal at a first side of a semiconductor die to a leadframe, the semiconductor die having a second load terminal at a second side opposite the first side and a control terminal at the first side or the second side; and encapsulating the semiconductor die in a laser-activatable mold compound so the leadframe is at least partly exposed from the laser-activatable mold compound at a first side of the molded semiconductor package, and the second load terminal is at least partly exposed from the laser-activatable mold compound at a second side of the molded semiconductor package.

Wafer-level stack chip package (assignee: Amkor Technology) patent no. 17/028329. A semiconductor product in the form of a stack chip package and a method of manufacturing the same, where a plurality of semiconductor chips are stacked one on another to enable the exchange of electrical signals between the semiconductor chips, and where a conductive layer is included for inputting and outputting signals to and from individual chips. A stack chip package having a compact size, a second semiconductor chip having a smaller surface area by means of interconnection structures to enable the exchange of electrical signals between the first and second semiconductor chips, and by using a conductive layer for inputting and outputting signals.

Optical device including buried optical waveguides and output couplers (assignee: Intel Corp.) pub. no. EP3767351. Embodiments of the present disclosure are directed toward techniques and configurations for an optical coupler, including an optical waveguide to guide light to an optical fiber. In embodiments, the optical waveguide includes a tapered segment to propagate the received light to the optical fiber. In embodiments, the tapered segment is buried below a surface of a semiconductor substrate to transition the received light within the semiconductor substrate from a first optical mode to a second optical mode to reduce a loss of light during propagation of the received light from the optical waveguide to the optical fiber. In embodiments, the surface of the semiconductor substrate comprises a bottom planar surface of a silicon photonic chip that includes at least one or more passive or active photonic components.

Gary Miller is technology analyst at IEEC, Binghamton University. He has over 40 years’ experience in electronic packaging. He previously was the chief mechanical engineer at Lockheed Martin;
The Integrated Electronics Engineering Center (IEEC) at Binghamton University is a New York Center of Advanced Technology (CAT) responsible for the advancement of electronics packaging. Its mission is to provide research into electronics packaging to enhance our partners’ products, improve reliability and understand why parts fail. Research thrusts are in 2.5/3-D packaging, automotive and harsh environments, bioelectronics, flexible and additive electronics, materials for packaging and energy storage, MEMS, photonics, power electronics, sensors, embedded electronics, and thermal challenges in electronic packaging. More information is available at