A5052876062- Electronic Packaging and Soldering Technologies
- 3D IC and TSV technologies
- Advanced Welding Techniques Analysis
- Advanced MEMS and NEMS Technologies
- Intermetallics and Advanced Alloy Properties
- Acoustic Wave Resonator Technologies
- Semiconductor materials and devices
- GaN-based semiconductor devices and materials
- Metal and Thin Film Mechanics
- Integrated Circuits and Semiconductor Failure Analysis
- Copper Interconnects and Reliability
- Adhesion, Friction, and Surface Interactions
- Mechanical and Optical Resonators
- Electrostatic Discharge in Electronics
- Aluminum Alloy Microstructure Properties
- Nanofabrication and Lithography Techniques
- Electromagnetic Compatibility and Noise Suppression
- Mechanical Behavior of Composites
- Silicon and Solar Cell Technologies
- Semiconductor Lasers and Optical Devices
- Synthesis and properties of polymers
- Semiconductor materials and interfaces
- Force Microscopy Techniques and Applications
- Modular Robots and Swarm Intelligence
- Silicon Carbide Semiconductor Technologies
Aalto University
2016-2025
Tieto (Finland)
2020-2024
Joint Research Center
2022
IBM (United States)
2013-2015
Gorgias Press (United States)
2013-2015
Cisco Systems (United States)
2013-2015
Tennessee Technological University
2013-2015
Qualcomm (United States)
2014-2015
University of Greenwich
2014-2015
Hong Kong University of Science and Technology
2013
While in use, battery modules and packs generate large amounts of heat, which needs to be accounted for. The main challenge thermal management is the correct estimation heat generation cell during charging/discharging. In this paper, a method calculate accurate one individual provided. calculated by measuring overpotential resistances with four different methods entropic cell. effect contribution towards total are also measured. Finally, calorimeter tests carried out compare measured...
Atomic-layer-deposited alumina (ALD Al2O3) can be utilized for passivation, structural, and functional purposes in electronics. In all cases, the deposited film is usually expected to maintain chemical stability over lifetime of device or during processing. However, as-deposited ALD Al2O3 typically amorphous with poor resistance attack by aggressive solutions employed electronics manufacturing. Therefore, such films may not suitable further processing as solvent treatments could weaken...
The mechanical reliability of the future miniaturized interconnects is mainly governed by intermetallic compounds such as Cu6Sn5. Alloyed Cu6Sn5 with various elements, including Co and In, have been introduced attracted attention for different reasons, enhancing lowering bonding temperature. Hence, this work aimed to evaluate microstructural properties Cu6Sn5-, Cu6(Sn,In)5-, (Cu,Co)6Sn5-, (Cu,Co)6(Sn,In)5-interconnects. grain size, orientation, crystal structure pure alloyed phases were...
This paper presents the reliability assessment of a three-axis microelectromechanical systems (MEMS) gyroscope subjected to various shock loading conditions. The tests include three different impact orientations and several acceleration levels impact, ranging from 1500 15 000 g. package failure functional MEMS devices are studied separately. analysis shows failures device at level above 8000 g caused by stiction or fractures in comb structure moderate around 4000 To have comprehensive...
Scandium-alloying of aluminum nitride (AlScN) enhances the piezoelectric properties material and increases performance microelectromechanical systems (MEMS). However, this enhancement is caused by destabilization wurtzite phase so far stability AlScN thin films has not been sufficiently studied. Stability especially important for devices because changes to film microstructure or residual stress can lead drastic in device behavior. The investigated annealing sputtered characterizing resulting...
Resonating piezoelectric devices, such as aluminum nitride (AlN) micromachined ultrasonic transducers (PMUTs), display superior performance to previous generations of resonating microelectromechanical systems (MEMS). However, the quality thin film can greatly impact operating characteristics, resonant frequency. Several AlN PMUT devices fabricated on same silicon wafer exhibited a range resonance frequencies (400-600 kHz), indicating that there is nonuniformity across processed wafer. likely...
Abstract Aluminum nitride (AlN) grown on vertical surfaces can be utilized for the fabrication of advanced piezoelectric microelectromechanical systems (MEMS). The in‐plane motion parts a MEMS element is possible when AlN deposited moving structure. For best device performance, must have high crystal quality, uniform coverage sidewalls, and c‐axis crystalline orientation perpendicular to plane surface. impact surface roughness ( R q ) sidewalls formed in Si using wet dry etching methods...
Heat accumulation and self-heating have become key issues in microelectronics owing to the ever-decreasing size of components move toward three-dimensional structures. A significant challenge for solving these is thermally isolating materials, such as silicon dioxide (SiO2), which are commonly used microelectronics. The silicon-on-insulator (SOI) structure a great demonstrator limitations SiO2 low thermal conductivity insulator prevents heat dissipation through bottom device built on SOI...
Atomic layer deposition (ALD) of aluminum nitride (AlN) using in situ atomic annealing (ALA) is studied for microelectromechanical systems (MEMS). Effective piezoelectric in-plane actuation and sensing requires high crystal quality (0002) oriented AlN on vertical sidewalls MEMS structures. Previous studies have shown that the ALD can be significantly improved ALA but not conformal coverage or metal electrodes, which are required devices. In this study, thin films deposited Si, Al, Pt, etched...
In this work, a low-temperature wafer-level bonding process at 150 °C was carried out on Si wafers containing 10 µm-sized microbumps based the Cu-Sn-In ternary system. Thermodynamic study shows that addition of enables low-melting temperature metals to reach liquid phase below melting point (157 °C) and promotes rapid solidification intermetallic layer, which are beneficial for achieving bonding. Microstructural observation high quality with low amount defect. SEM TEM characterization...
3D heterogeneous integration is becoming increasingly important in advanced packaging as device functionalities expand within smaller spaces. interconnects such Through Silicon Vias (TSVs)- Solid-Liquid Inter-Diffusion (SLID) offer a promising approach for achieving miniaturization, high integration, and reduced power consumption. However, well known Cu-Sn SLID-TSVs require bonding temperatures, leading to residual stress cracks. This research focuses on developing by using Cu-Sn-In/Co...
Plasma-enhanced atomic layer deposition was utilized to grow aluminum nitride (AlN) films on Si from trimethylaluminum and N2:H2 plasma at 200 °C. Thermal treatments were then applied the which caused changes in their chemical composition nanostructure. These observed manifest refractive indices densities of films. The AlN identified contain light element impurities, namely, H, C, excess N due nonideal precursor reactions. Oxygen contamination also Many embedded impurities became volatile...
Most micro-electro-mechanical systems (MEMS) devices contain fragile moving parts, which poses challenges in process integration of interconnection methods requiring wet-chemistry, such as solid-liquid interdiffusion bonding (SLID). These sensitive MEMS structures can be protected from either the wet-chemistry or plated metals during chemical/electro-chemical plating SLID materials; however, this is a complex process. Hence, our previous research has investigated employing physically...
The work presented in this paper focuses on a) clarifying the underlying physical failure mechanism of Sn-rich solder interconnections under thermomechanical loading and b) identifying means to accelerate by optimizing dwell-times ramp-rates thermal cycling test. statistical results showed that as were decreased number cycles increased but shortest testing time was achieved with 10-minute dwell-times. Increase ramp-rate did not affect significantly reduced. Investigations nucleation cracks...