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Bioactive Plastics With Programmable Degradation And Microplastic Elimination

Although the plastic waste crisis has reached a breaking point, current recycling approaches are unable to remediate microplastic pollution. Biodegradable and renewable plastics have shown promise but impact neither microplastic elimination nor complete plastic recycling due to diffusion-limited enzymatic surface erosion and random chain scission. Here it is shown that nanoscopic dispersion of trace enzyme (e.g. lipase) in plastics (e.g. polycaprolactone [PCL]) leads to fully functional plastics with eco-friendly microplastic elimination and programmable degradation. Nanoscopic enzyme encapsulation leads to:continuous degradation to achieve 95% microplastic eliminationa single chain-based degradation mechanism with repolymerizable small molecule by-products via selective chain end scission rather than random chain scissionspatially- and temporally-programmable degradation of melt-processed host matrix due to the dependence of single chain degradation on local lamellae thickness regardless of bulk percent crystallinity formulation of conductive ink for 3-D printing with full recovery of the precious metal filler With recent developments in synthetic biology and genome information, nanoscopically embedding catalytically active enzymes in plastics may lead to an immediate, environmentally friendly and technologically viable solution toward microplastic elimination and material recycling.

Diamond On Nanopatterned Substrates

UCLA researchers in the Department of Materials Science and Engineering have developed a nanofabrication method for improving the thermal properties of polycrystalline diamond films grown by chemical vapor deposition.

Magnetoelectric Device with Two Dielectric Barriers

UCLA researchers in the Department of Electrical and Computer Engineering have developed a magnetoelectric memory device that uses two dielectric barriers for improved voltage-controlled magnetic anisotropy (VCMA) and tunnel magnetoresistance (TMR) properties.

Selective Deposition Of Diamond In Thermal Vias

UCLA researchers in the Department of Materials Science & Engineering have developed a new method of diamond deposition in integrated circuit vias for thermal dissipation.

A Nonvolatile Magnetoelectric Random Access Memory Circuit

UCLA researchers in the Department of Electrical Engineering have developed a nonvolatile random-access memory circuit (MeRAM) that is very dense, fast, and consumes extremely low power.

Voltage-Controlled Magnetic Memory Element With Canted Magnetization

UCLA researchers in the Department of Electrical Engineering have developed a method for voltage-controlled switching of the magnetization direction in MeRAM circuits.

Electrical Conduction In A Cephalopod Structural Protein

Fabricating materials from naturally occurring proteins that are inherently biocompatible enables the resulting material to be easily integrated with many downstream applications, ranging from batteries to transistors. In addition, protein-based materials are also advantageous because they can be physically tuned and specifically functionalized. Inventors have developed protein-based material from structural proteins such as reflectins found in cephalopods, a molluscan class that includes cuttlefish, squid, and octopus. In a space dominated by artificial, man-made proton-conducting materials, this material is derived from naturally occurring proteins.

A Low-Cost-Wafer-Level Process For Packaging MEMS 3-D Devices

A low-cost solution to robust electronic packaging of 3-D MEMS devices using micro-glassblown “bubble-shaped” structures.

Mechanical Process For Creating Particles Using Two Plates

UCLA researchers in the Department of Chemistry and Biochemistry & Physics and Astronomy have developed a novel method to lithograph two polished solid surfaces by using a simple mechanical alignment jig with piezoelectric control and a method of pressing them together and solidifying a material.

Hemispherical Rectenna Arrays for Multi-Directional, Multi-Polarization, and Multi-Band Ambient RF Energy Harvesting

UCLA researchers in the Department of Electrical Engineering have developed a system that can receive RF waves in different frequency bands, from different directions, and with different polarizations to maximize energy harvested from ambient radio-frequency signals.

RF-Powered Micromechanical Clock Generator

Realizing the potential of massive sensor networks requires overcoming cost and power challenges. When sleep/wake strategies can adequately limit a network node's sensor and wireless power consumption, then the power limitation comes down to the real-time clock (RTC) that synchronizes sleep/wake cycles. With typical RTC battery consumption on the order of 1µW, a low-cost printed battery with perhaps 1J of energy would last about 11 days. However, if a clock could bleed only 10nW from this battery, then it would last 3 years. To attain such a clock, researchers at UC Berkeley developed a mechanical circuit that harnesses squegging to convert received RF energy (at -58dBm) into a local clock while consuming less than 17.5nW of local battery power. The Berkeley design dispenses with the conventional closed-loop positive feedback approach to realize an RCT (along with its associated power consumption) and removes the need for a sustaining amplifier altogether. 

Efficient Supercapacitator Charging Technique by a Hysteretic Charging Scheme

The technology is a hysteretic charging technique for efficient supercapacitor charging using low ambient power sources.With this technology user may extend the upper bound on the capacitance of supercapacitors.The technology features hysteretic control, a two stage supercapacitor system.Additionally, the technology features a pulse-frequency modulation (PFM) dc-dc boost converter.

An All Solid-State Wafer Bonding Method Of III-V Materials On Si CMOS Using Patterned Metal Structures

III-V compound semiconductor materials comprise elements from the third group (such as Al, Ga, and In) and fifth group (such as N, P, As, and Sb) of the periodic table. It has become a trend for both scientific research and semiconductor industry to combine the high-speed III-V semiconductors as both electronic and optoelectronic devices with low-cost Si circuitry. Integration of III-V functional devices on Si substrates was generally achieved by epitaxial growth of III-V material layers on Si, or by directly bonding of III-V semiconductor layers with the Si wafer. Most methods are not compatible with CMOS process due to their complicated procedures, or strong changes to the surface morphology of bonding layer, set aside the ability to arbitrarily define structures at any location and with any shape in a planar CMOS-like fabrication process. Presently need an improved way to:(1) integrate III-V semiconductors onto Si that is compatible with current CMOS fabrication procedure,(2) cause minimum or zero crystal defects to the bonded semiconductor layers, and(3) enable further fabrication of advanced functional devices using the bonded layers atop functional CMOS circuitry without degraded performance.

Self-Limiting CVD of Silicon Monolayer for Preparation of Subsequent Silicon or Gate Oxide ALD on III-V Semiconductor and Metal Surfaces

Two of the leading materials considered for use in post silicon n-channel regions of planar-FETs and finFETs are SiGe and InGaAs, as both of these alternatives contain high intrinsic electron mobilities. A broader range of channel materials allowing better carrier confinement and mobility could be employed if a universal control monolayer (UCM) could be atomic layer deposited (ALD) or self-limiting chemical vapor deposited (CVD) on multiple materials and crystallographic faces. The existing silicon ALD process is not self-limiting.

Vertical Heterostructures for Transistors, Photodetectors, and Photovoltaic Devices

The Duan group at UCLA has developed a high current density vertical field-effect transistor (VFET) that benefits from the strengths of the incorporated layered materials yet addresses the band gap problem found in current graphene technologies.

Magnetically Controlled Casting Process

Current casting methods that produce features in a solid material with rapid prototyping techniques require highly specialized and expensive equipment.  Further, these types of equipment must be programmed before each casting to achieve the desired results.  Also, these traditional casting processes are synthesized either through layer-by-layer deposition which can be very time consuming or by mixing non-soluble components together which leads to heterogeneities and reduction in performance.                                                  

A Novel High-Qu Octave-Tunable Resonator And Filter With Lumped Tuning Elements

This invention utilizes standard printed circuit board (PCB) fabrication technology to create a novel high-quality factor (Qu) continuously-tunable resonator and filter. The inherent benefits of the proposed design are: 1) flexibility in choosing various types of tuning components (e.g. solid-state, ferroelectric, and radio frequency microelectromechanical systems (RF MEMS) varactors), 2) compared to traditional cavity tunable resonators, the initial starting frequency is primarily determined by the tuning element as opposed to precise assembly techniques, and 3) industry-standard PCB substrates with commercially-available tuning components are used, thereby facilitating high-volume manufacturing, ease of integration with other RF front-end components and lower fabrication costs. A tunable resonator and two-pole bandpass filter with solid-state varactors are designed and fabricated to experimentally validate the approach. The resonator surpasses the state-of-the-art with a frequency tuning range of 0.5–1.2 GHz (tuning ratio of 2.4 : 1) and a Qu of 82–197. The bandpass filter exhibits frequency tuning of 0.57-1.17 GHz, insertion loss of 4.9-1.9 dB and a 3-dB bandwidth of 2-8 %. Lastly, an RF MEMS varactor enabled tunable resonator based on the same design further shows Quof 240 at 6.6 GHz.

Origamic Topology for Analog and Mixed-Signal Circuit Applications

UCLA researchers in the Department of Electrical Engineering have developed and reduced-to-practice an innovative circuit structure for low power consumption and high gain amplification. 

A Method for Making Low-Cost Silicon Devices with Reduced Inactive Area

Modern semiconductor detectors have been developed for sensing light, X-rays and charged particles. Such devices have established broad applications because of their reliability, and compactness. However, they typically contain an inactive area near the edges of the device. This scheme allows for dicing of the wafers (thin slices of semiconductor material) resulting in large device defect densities. Also, the existence of up to a 1mm wide inactive band leads to efficiency gaps when a larger surface is covered with many such devices. Researchers at UCSC in collaboration with the U.S. Naval Research Laboratory (NRL) have developed methods for fabricating resistive semiconductor sidewalls near the active area that allow deep depletion operation. These methods can be used to make compact, low-cost sensor devices without inactive periphery. Moreover, this robust and scalable method could be used for IC (integrated circuit) production, power electronics IC production, radiation detector (or sensor) production, imaging sensors, and solar cell production.    

Augmentation Of Conventional Passive Heat Transfer

As powered electrical and mechanical devices have continued to be miniaturized, it has become increasingly important to limit the temperature rises of vulnerable components such as integrated circuits, small mechanical elements and light sources. The conventional passive heat transfer method most commonly used is to simply put a set of fins in the heat transfer path from the source of heat (e.g., a packaged device) to a region where a gaseous or liquid coolant contacts the fins, becomes heated, and then is allowed to contact or mix with a large volume of gas or liquid that is cooler. These finned heat transfer approaches have limits, and therefore researchers at UC Berkeley have developed a means of augmenting this conventional passive heat transfer with supplementary actively powered mechanisms. This novel approach increases the rate of contact and mixing -- and thereby, the rate of heat removal. The approach is appropriately sized (i.e., miniature), energy efficient, quiet, inexpensive, and has a long lifetime. 

Phase Coherent Frequency Divider

Phase-coherent differential structures contain a phase-coherent transformer having two pairs of phase-coherent coupled differential inductors.

Improved Mechanical Contact Reliability and Energy Efficiency for CMOS Applications

In order to overcome fundamental energy efficiency limits of CMOS technology, micro-electro-mechanical (MEM) relay technologies are now being investigated for ultra-low-power digital integrated circuit (IC) applications. High relay endurance (exceeding 10^14 ON/OFF switching cycles) is required for relay-based ICs to be viable, and has been a major challenge due to stiction and wear. Researchers at UC Berkeley have developed an efficient way to reduce contacts aging, stiction, and oxidation. The researchers have shown that contacts can be made to be very reliable with very low resistance. To date, a contact resistance of 85.2 kohms has been measured at room temperature and suggests the possible use of these contacts for relay-based integrated circuits, which typically requires contact resistances less than 100 kohms. Further work will include coating optimization, surface roughness analysis, dynamic measurements for contact aging evaluation, thermal analysis, extraction of the effective contact area, and advanced current transport modeling.

Zero-footprint Metrology Microsystem

In order to enable the reliable reproducibility of micro-scale devices used in high volume, low cost integrated circuit manufacturing, process parameters need to be directly measured and monitored during manufacturing. Probing optical beams that are directed from external photo sources have been used to probe in-situ information such as film thickness, material density, and refractive index. However in hostile processing situations that include plasmas, corrosive solutions, or polishing slurries, the environment interferes with these optical beams and consequently makes this approach infeasible. To address this problem, researchers at UC Berkeley have developed a new optical metrology microsystem that can be used in hostile environments. This microsystem can be implemented in a form-factor varying from a stand-alone mot-size device to a metrology wafer with an array of these metrology microsystems. To ensure accurate and precise measurements, an original implementation design and a dedicated data analysis algorithm have been developed that makes it possible to eliminate various implementation errors. The Berkeley researchers have successfully implemented this system in a prototype wafer with 3 x 3 metrology cells. Reflectance measurements showed that the system design and analysis algorithm works. Additionally, this prototype was calibrated using a SF6 plasma etching process of silicon oxide -- which further confirmed the validity of this design and methodology.

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