Characterization and Benchmark of a Novel Capacitive and Fluidic Inclination Sensor

In this paper, a fluidic capacitive inclination sensor is presented and compared to three types of silicon-based microelectromechanical system (MEMS) accelerometers. MEMS accelerometers are commonly used for tilt measurement. They can only be manufactured by large companies with clean-room technology due to the high requirements during assembly. In contrast, the fluidic sensor can be produced by small- and medium-sized enterprises (SMEs) as well, since only surface mount technologies (SMT) are required. Three different variants of the fluidic sensor were investigated. Two variants using stacked printed circuit boards (PCBs) and one variant with 3D-molded interconnect devices (MIDs) to form the sensor element are presented. Allan deviation, non-repeatability, hysteresis, and offset temperature stability were measured to compare the sensors. Within the fluidic sensors, the PCB variant with two sensor cavities performed best regarding all the measurement results except non-repeatability. Regarding bias stability, white noise, which was determined from the Allan deviation, and hysteresis, the fluidic sensors outperformed the MEMS-based sensors. The accelerometer Analog Devices ADXL355 offers slightly better results regarding offset temperature stability and non-repeatability. The MEMS sensors Bosch BMA280 and TDK InvenSense MPU6500 do not match the performance of fluidic sensors in any category. Their advantages are the favorable price and the smaller package. From the investigations, it can be concluded that the fluidic sensor is competitive in the targeted price range, especially for applications with extended requirements regarding bias stability, noise, and hysteresis.

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Can’t Touch This: Inertial HSMs Thwart Advanced Physical Attacks

IACR Transactions on Cryptographic Hardware and Embedded Systems ◽

10.46586/tches.v2022.i1.69-93 ◽

2021 ◽

pp. 69-93

Author(s):

Jan Sebastian Götte ◽

Björn Scheuermann

Keyword(s):

High Speed ◽

Printed Circuit Boards ◽

Hardware Security ◽

Moving Target ◽

Proof Of Concept ◽

Circuit Boards ◽

Printed Circuit ◽

Mems Accelerometers ◽

Conventional Systems ◽

Hardware Security Modules

In this paper, we introduce a novel countermeasure against physical attacks: Inertial Hardware Security Modules (IHSMs). Conventional systems have in common that their security requires the crafting of fine sensor structures that respond to minute manipulations of the monitored security boundary or volume. Our approach is novel in that we reduce the sensitivity requirement of security meshes and other sensors and increase the complexity of any manipulations by rotating the security mesh or sensor at high speed—thereby presenting a moving target to an attacker. Attempts to stop the rotation are easily monitored with commercial MEMS accelerometers and gyroscopes. Our approach leads to an HSM that can easily be built from off-the-shelf parts by any university electronics lab, yet offers a level of security that is comparable to commercial HSMs. We have built a proof-of-concept hardware prototype that demonstrates solutions to the concept’s main engineering challenges. As part of this proof-of-concept, we have found that a system using a coarse security mesh made from commercial printed circuit boards and an automotive high-g-force accelerometer already provides a useful level of security.

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Development and Validation of a Novel Setup for LEDs Lifetime Estimation on Molded Interconnect Devices

Instruments ◽

10.3390/instruments2040028 ◽

2018 ◽

Vol 2 (4) ◽

pp. 28 ◽

Cited By ~ 1

Author(s):

Mahdi Soltani ◽

Moritz Freyburger ◽

Romit Kulkarni ◽

Rainer Mohr ◽

Tobias Groezinger ◽

...

Keyword(s):

Printed Circuit Boards ◽

Functional Integration ◽

Consumer Electronics ◽

Light Sources ◽

Circuit Boards ◽

Light Emitting ◽

Compact Design ◽

Long Term Behavior ◽

Molded Interconnect Devices

Higher energy efficiency, more compact design, and longer lifetime of light-emitting diodes (LEDs) have resulted in increasing their market share in the lighting industry, especially in the industries of consumer electronics, automotive, and general lighting. Due to their robustness and reliability, LEDs have replaced conventional light sources, such as fluorescent lamps. Many studies are examining the reliability of LEDs as such or investigating their long-term behavior on standard printed circuit boards (PCB). However, the thermal performance of LEDs mounted on nonconventional substrates is still not explored enough. An interesting example for this is the molded interconnect devices (MID), which are well known for the great design freedom and the great potential for functional integration. These characteristics not only underline the main abilities of the MID technology, but also present some challenges concerning thermal management. The long-term behavior of LEDs on MID is still quite untapped and this prevents this technology from consolidating its existence. In this context, this work highlights a developed test setup aimed at investigating LEDs, mounted on molded interconnect devices, under combined stress conditions. The results of the reliability study, as well as the resulting lifetime model, are also illustrated and discussed.

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Packaging Technology of Multi Deflection Arrays for Multi-Shaped Beam Lithography

International Symposium on Microelectronics ◽

10.4071/isom-2011-wa5-paper1 ◽

2011 ◽

Vol 2011 (1) ◽

pp. 000600-000607 ◽

Cited By ~ 1

Author(s):

T. Burkhardt ◽

M. Mohaupt ◽

M. Hornaff ◽

B. Zaage ◽

E. Beckert ◽

...

Keyword(s):

Electron Beam ◽

Degrees Of Freedom ◽

Printed Circuit Boards ◽

Electrical Signal ◽

Beam Deflection ◽

Circuit Boards ◽

Direct Writing ◽

Soldering Process ◽

Flexible Printed Circuit ◽

Silicon Based

Multi-Shaped electron beam lithography is considered a promising approach for high throughput mask and direct writing. Providing multiple apertures and individually controlled electrodes it allows for massive parallelization of exposure shots, thus significantly decreasing write time. A silicon-based micro-structured MEMS multi-beam deflection array (MDA) featuring 8×8 apertures is presented. The hybrid integration of MDA devices in ceramic system carriers utilizing a laser-based Solderjet Bumping process is demonstrated. This flux-free soldering process provides adhesive-free, long term stable and vacuum compatible joints and is used for both mechanical fixation and electrical connection. Electron beam deflection in two perpendicular directions requires the highly accurate placement of two crossed MDA devices, which is carried out by three degrees of freedom alignment procedures and solder joining. Electrical signal routing within the electron optical column using flexible printed circuit boards and flux-free soldering is also reported. The precision adjustment of two carriers is accomplished by fiducial mark detection using image processing. Results on alignment accuracy in the sub-micron range, mechanical and electrical testing of such assemblies are reported.

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