IEEC
State-of-the-Art Technology Flashes
Updates in silicon and electronics technology.
Ed.: This is a special feature courtesy of Binghamton University.
Integrated photonic circuits demonstrate ultralow loss. EPFL researchers have developed a technology that produces silicon nitride integrated photonic circuits with low optical losses and small footprints. Silicon nitride has been a material of choice for applications where low loss is critical, such as narrow-linewidth lasers, photonic delay lines, and those in nonlinear photonics. The team combined nanofabrication and material science based on the photonic Damascene process developed at EPFL. With this process, the team made integrated circuits of optical losses of 1dB/m, a record value for any nonlinear integrated photonic material. That low loss considerably reduces the power budget for building chip-scale optical frequency combs used in applications that include coherent optical transceivers, low-noise microwave synthesizers, lidar, neuromorphic computing and optical atomic clocks. (IEEC file #12282, Photonics Media, 5/6/21)

Samsung develops advanced chip packaging tech. Samsung Electronics has developed an advanced chip packaging technology for high-performance applications. Its next-generation 2.5D packaging technology, Interposer-Cube4 (I-Cube4), is expected to be widely used in areas like high-performance computing, artificial intelligence, 5G, cloud and data centers with enhanced communication and power efficiency between logic and memory chips. I-Cube is heterogeneous integration technology that horizontally places one or more logic dies, such as CPU and GPU, and several high bandwidth memory dies on a paper-thin silicon interposer. (IEEC file #12285, Science Daily, 5/6/21)

graphic of advanced chip packaging components
Reconfigurable optical networks will move supercomputer data 100X faster. Supercomputer processors can handle large amounts of data per second, but the flow of data between the processor and computer subsystems is not as efficient, creating a data transfer bottleneck. Peraton Labs researchers have devised a system design involving reconfigurable networks called FLEET, which could potentially speed up the transfer of data 100-fold. The team’s solution was the development of optical network interface cards (O-NICs) that plug into existing computer hardware. Whereas traditional NICs typically have one port, the newly designed O-NICs have two ports and can support data transfer among many kinds of computer subcomponents. The O-NICs are connected to optical switches, which allow reconfiguring the data flow. (IEEC file #12288, IEEE Spectrum, 5/7/21)

Silicon chips combine light and ultrasound for better signal processing. High-end wireless and cellular networks rely on light for signal distribution. The selective processing of such signals requires long delays, too long to support on a chip using light alone. Hebrew University of Jerusalem researchers brought together light and ultrasonic waves to develop ultra-narrow filters of microwave signals in silicon integrated circuits. The information-carrying surface acoustic waves is imprinted upon the output light wave multiple times. The concept permits large freedom for filter design. (IEEC file #12307, Science Daily, 5/20/21)

Self-healing gels could power future electronics. For flexible ion gels to become critical components in wearable and stretchable electronic devices, they must be able to withstand repeated mechanical deformation, such as bending or stretching. Ion gels are made of a polymer matrix containing ionic liquids: room temperature molten salts containing positively and negatively charged ions. Ionic liquids are being considered for use in a variety of electronic devices, including supercapacitors, rechargeable lithium batteries, fuel cells and soft robotics. The repairable ion gels are made by adding the compound azobenzene. Exposing the damaged gel to ultraviolet light changes it into a liquid that fills the damaged region. Then exposing it to visible light restores the gel damaged section to its original state. (IEEC file #12287, Nanowerk, 5/12/21)

image sequence of gel cut, healed and stretched
Aluminum batteries take a step closer. Cornell University researchers have taken a step closer to aluminum batteries that can be used in grid-scale storage. Aluminum is more plentiful and cheaper that lithium, making it potentially attractive for large-scale energy storage. Aluminum also has the advantage over lithium that it can be used in metallic form without the safety concerns that metallic lithium arouses. The team also studied why aluminum batteries develop short-circuits and die after only a few charge-discharge cycles. They found that tall, sparsely spaced aluminum peaks grew on the stainless steel in a few charge-discharge cycles, pushing through the glass fiber and shorting the opposite aluminum electrode. (IEEC file #12224, Electronics Weekly, 4/9/21)

Engineers harvest Wi-Fi signals to power small electronics. National University of Singapore researchers have developed a technology that uses tiny smart devices known as spin-torque oscillators (STOs) to harvest and convert wireless radio frequencies into energy to power small electronics. They successfully harvested energy using Wi-Fi 33-band signals to power a LED wirelessly, and without a battery. This is a step toward turning readily available 2.4GHz radio waves into a green source of energy, reducing the need for batteries to power electronics. In this way, small electric gadgets and sensors can be powered wirelessly using radio frequency waves as part of the Internet of Things. (IEEC file #12302, Science Daily, 5/14/21)

DRAM replacement unveiled. Unisantis Electronics has developed dynamic flash memory (DFM), a faster and denser technology than DRAM (or other types of volatile memory). DFM takes a revolutionary approach to overcome limitations of conventional volatile memory with its inherent short refresh cycles and destructive read processes. DFM is also a type of volatile memory, but since it does not rely on capacitors, it has fewer leak paths and no connection between switching transistors and a capacitor. The result is a cell design with the potential for significant increases in transistor density, and it offers block erase. (IEEC file #12303, Science Daily, 5/14/21)

diagram showing the structure of dynamic flash
Research breakthrough in 5-nanometer transistors. IBM and its partners GlobalFoundries and Samsung have developed a first-of-a-kind process to build silicon nanosheet transistors that will enable 5nm chips. The breakthrough involved stacking so-called nanosheets to build the 5nm transistors instead of the current FinFET process used to make 7nm transistors. Such an increased transistor density gives the 5nm chip a 40% performance boost and enables 75% power efficiency at the same performance level. The resulting increase in performance will help accelerate cognitive computing, IoT and other data-intensive applications delivered in the cloud. The power savings could mean batteries in smartphones and other mobile products could last two to three times longer than today’s devices before needing to be charged. (IEEC file #12305, Electronic Design, 5/24/21)

Nano diamond battery provides universal applicability. The nano diamond battery (NDB) is a high-power, diamond-based alpha, beta, and neutron voltaic battery that can provide lifelong and green energy for numerous applications and overcome limitations of existing chemical batteries. The NDB acts like a tiny nuclear generator. The power source for the NDB is intermediate- and high-level radio isotopes shielded for safety by multiple levels of synthetic diamond. Energy is absorbed in the diamond through a process called inelastic scattering, which is used to generate electricity. The self-charging process will provide a charge for the full lifetime of any device or machine, with up to 28,000 years of battery life. (IEEC file #12228, NASA Tech Briefs, 4/1/21)

close view of nano diamond battery
Market Trends
Printed electronics automotive market $12.7 billion by 2031. Opportunities for printed and flexible electronics are increasing from the transition to electric and autonomous vehicles. The printed electronics automotive market is predicted to be $12.7 billion by 2031. Technologies include sensors within EV batteries, interior HMI components, displays, and new manufacturing methods such as in-mold electronics. Hence, it is an exciting time for the automotive industry, with technological transitions toward electric vehicles and increased autonomy occurring simultaneously. (IEEC file #12291, Printed Electronics World, 5/5/21)

Compact, multifunctional device uses infrared light to deliver images. University of California researchers have developed a thin, large-scale device that converts infrared light into images. The imager can be used to see through smog and smoke, to see through silicon wafers to inspect the quality and composition of electronic boards, and to map a person’s blood vessels while monitoring heart rate. The imager detects the shortwave IR part of the spectrum and falls just outside the visible spectrum. In applications, it shines shortwave IR light on an object and then converts the low-energy IR light that is reflected to the device into shorter, higher-energy wavelengths that are visible. Three of the layers are made of a different organic polymer: a photodetector layer, an OLED display layer, and a layer located between that blocks electrons. (IEEC file #12299, Photonics Media, 5/7/21)

Wind-powered streetlight only turns on when you pass it. Berlin University of the Arts researchers have created a streetlight called “Papilio” that combats energy pollution on two fronts: It’s wind-powered, which reduces its dependence on electricity, and the light itself has a motion sensor that’s only activated when someone passes underneath it. Some 60% of the electricity used is produced from fossil fuels. Roughly 83% of the world’s population lives under artificial lights that brighten the sky 10% more than its normal level, which can negatively impact biodiversity. (IEEC file #12315, Electronics Weekly, 5/21/21)

(left) wind powered street lamp mockup, (right) man works on wind powered street lamp
Smart finger ring with integrated RFID. The smart finger ring multifunctional ring was developed by Fraunhofer IGCV researchers. Produced by a 3-D printing process using “powder bed-based additive manufacturing,” the ring has an integrated RFID chip, and is tamperproof, sealed, and invisible. This precisely controllable production technology is opening the door to a host of possibilities for realizing individualized ring designs. The technology of integrating electronics via 3-D printing can be used for many other applications. The RFID tag can pay at checkout, open a smart front door, act as a health insurance card when attending a medical appointment, or replace the key card in a hotel. (IEEC file #12295, Printed Electronics World, 5/7/21)

Memory market to reach $155 billion in 2021; $180 billion in 2022. A stronger DRAM pricing is expected to lift total memory revenue 23% this year to $155.2 billion. The DRAM ASP rose 8% in Q1 2021, and nearly all the leading memory suppliers expected stronger demand in Q2. The memory upturn is forecast to continue into 2022 when total memory sales are expected to rise 16% to $180.4 billion. The memory market is forecast to reach its next cyclical peak in 2023, when revenue grows to nearly $220 billion. In 2021, DRAM is expected to account for 56% of the memory market, with flash memory accounting for 43% share. (IEEC file #12312, Electronics Weekly, 5/21/21)

Photovoltaic roof for highways. Fraunhofer Institute researchers have developed a photovoltaic (PV) system for motorways and are testing how roofs may be deployed along highways. The demonstrator consists of a PV system with a 10 x 17m roof area installed on a steel structure about 5.5m above the road. Construction on the pilot project is expected to begin next autumn, and its operations then will be monitored for about a year. The roofing of a motorway is a particular technical challenge because of the fast-moving traffic underneath. (IEEC file #12318, PV Magazine, 5/26/21)

a photovoltaic roof stands over the right side of a highway
Scientists develop transparent electrode that boosts solar cell efficiency. Penn State University researchers are developing an ultrathin metal electrode that permits creation of semitransparent perovskite solar cells that are highly efficient and can be coupled with traditional silicon cells to greatly boost the performance of both devices. The research is a major step toward developing completely transparent solar cells. Transparent solar cells could find a place on windows in homes and office buildings, generating electricity from sunlight. Perovskite cells offer a promising alternative, and stacking them on top of the traditional cells can create more efficient tandem devices. The perovskite solar cell the team developed achieved 19.8% efficiency. Combined with a traditional silicon solar cell, the tandem device achieved 28.3% efficiency, up from 23.3% from the silicon cell alone. (IEEC file #12307, Science Daily, 5/28/21)
Recent Patents
Additively manufactured flexible interposer (assignee: Boeing Corp.) patent. no. 16/390,256. The method includes providing a flexible interposer, providing a first redistribution layer on the flexible interposer, and providing a second redistribution layer on a portion of the first redistribution layer. The second redistribution layer is provided by additive manufacturing. The first redistribution layer may be deposited in a clean room environment. The first redistribution layer may be deposited via chemical or physical deposition. A semiconductor device is attached to the first redistribution layer. The flexible interposer may be attached to a board with the semiconductor device electrically connected to the board via the first redistribution layer, the flexible interposer, and the second redistribution layer. The flexible interposer may be attached to a flexible hybrid electronic (FHE) board. The flexible nature of the flexible interposer and/or the FHE board may redistribute stress on the semiconductor device assembly.

Optical coupling of optical signals for a photonic integrated circuit (assignee: Mellanox Technologies) patent no. 16/313,503. An optical coupler and method of assembly are described that provide efficient coupling from the photonic IC (PIC) waveguide layer to external components, such as optical fibers, VCSELs, photodetectors, and gain blocks, among others. The optical coupler includes a PIC that can be supported by a printed circuit board, an optoelectronic transducer supported by the PIC that can convert between optical signals and corresponding electrical signals, and a coupled waveguide assembly. The coupled waveguide assembly includes a low-index waveguide, a high-index waveguide, and a reflective surface that changes a pathway of the optical signals to direct the optical signals from the optoelectronic transducer into the low-index waveguide or from the low-index waveguide into the optoelectronic transducer.

PCB assembly comprising chemical vapor CVDD wires for thermal transport (assignee: Microchip Technology) pub. no. WO / 2021089974. A method and apparatus for conducting heat away from a semiconductor die are disclosed. A board assembly is disclosed that includes a circuit board, a semiconductor die electrically coupled to the circuit board and a chemical vapor deposition diamond (CVDD) coated wire. A portion of the CVDD-coated wire extends between a hot-spot on the semiconductor die and the circuit board. The board assembly includes a layer of thermally conductive paste that is disposed between the hot spot on the die and circuit board. The layer of thermally conductive paste is in direct contact with a portion of the CVDD-coated wire.

Wafer-level derived flip-chip package (assignee: Texas Instruments) patent. no. 11,018,111. A leadless IC package includes a spaced apart plurality of lead terminals on at least two sides of the leadless IC package, and a die including a substrate having at least a semiconductor surface including circuitry coupled to bond pads with the bond pads having bonding features thereon. The bonding features are flip-chip bonded to the plurality of lead terminals. Mold compound is above the IC die and between adjacent lead terminals. The lead terminals and the substrate both extend out to have exposed surfaces at edges of the leadless IC package, and the terminals also provide a backside bondable contact.

Optical device including buried optical waveguides and output couplers (assignee: Intel Corp.) pub. no. US10996408. 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 the 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 light loss 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 of passive or active photonic components.

Hermetically sealed printed circuit boards (Assignee: Covidien LP) patent no. 10,973,142. A method of assembling a hermetically sealed printed circuit board includes securing a flange of a cap against an electrical contact region on the first side of a substrate, the flange extending across a first end portion of a wall of the cap, the wall extending around the electrical contact region and including a second end portion disposed in an open configuration, and closing the second end portion of the wall to form a hermetically sealed chamber around the electrical contact region.

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; gmiller@binghamton.edu.
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 binghamton.edu/ieec.