The discrete vacuum packaging of IR-microbolometers

2015 ◽  
Vol 2015 (DPC) ◽  
pp. 001123-001139
Author(s):  
Luca Mauri
Keyword(s):  
Inertial Sensors ◽  
Point Of View ◽  
Sensing Element ◽  
Micro Electro Mechanical Systems ◽  
Vacuum Sealing ◽  
Hermetic Packaging ◽  
Die Attach ◽  
Hermetic Sealing ◽  
Target Pressure ◽  
Device Lifetime

Packaging of Micro Electro Mechanical Systems (MEMS) requires technical challenges to be solved and overcome when stringent vacuum and hermetic sealing is required. This is typical for a wide class of devices, such as inertial sensors, MEMS atomic clocks, IR micro-bolometers, where such conditions need to be achieved to provide the performance stability during the lifetime of the devices. The most challenging vacuum requirements are related to micro-bolometers, since good vacuum level is needed for thermal insulation. Typical target pressure is ≈ 10-3 – 10-4 mbar. Vacuum hermetic packaging can be successfully achieved by dedicated getter film integration, key technology for vacuum requirements, in combination with a specific sealing process and choice of vacuum compatible materials. The discrete packaging of the device requires the attachment of the sensing element into a ceramic package, like LCC. Typically, adhesives are used as die attach material. From the vacuum point of view, adhesives are not ideal candidates and therefore the compatibility with stringent vacuum requirements is not always guaranteed. Preliminary outgassing tests on these components are recommended to select appropriate materials. Thermal treatment of components is another key point for vacuum sealing, since specific degassing treatments before and during sealing can effectively reduce the amount of gas inside the volume of the device. The getter film integration is mandatory in such kind of devices because of the stringent vacuum requirements. SAES' proprietary technology is fully compliant with micro-bolometer manufacturing and the optimization of the getter activation step, during the bonding process, enables the functionality of the device along its lifetime. Moreover, capabilities of performing residual gas analyses and leak rate measurements of sealed devices are fundamental for quality control of vacuum sealing as well as for analyses and prediction of device lifetime.

scholarly journals Formation of a Complex Topologies of SAW-Based Inertial Sensors by Laser Thin Film Local Evaporation

Micromachines ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 10
Author(s):  
Alexander Kukaev ◽  
Dmitry Lukyanov ◽  
Denis Mikhailenko ◽  
Daniil Safronov ◽  
Sergey Shevchenko ◽  
...  
Keyword(s):  
Thin Film ◽  
Acoustic Wave ◽  
Surface Acoustic Wave ◽  
Acoustic Waves ◽  
Inertial Sensors ◽  
Surface Acoustic Waves ◽  
Sensing Element ◽  
Small Series ◽  
Evaporation Technique ◽  
Photolithography Process

Originally, sensors based on surface acoustic waves are fabricated using photolithography, which becomes extremely expensive when a small series or even single elements are needed for the research. A laser thin film local evaporation technique is proposed to substitute the photolithography process in the production of surface acoustic wave based inertial sensors prototypes. To estimate its potential a prototype of a surface acoustic wave gyroscope sensing element was fabricated and tested. Its was shown that the frequency mismatch is no more than 1%, but dispersion of the wave on small inertial masses leads to a spurious parasitic signal on receiving electrodes. Possible ways of its neglecting is discussed.

Natural Locomotion Based on Foot-Mounted Inertial Sensors in a Wireless Virtual Reality System

2015 ◽  
Vol 24 (4) ◽  
pp. 298-321 ◽  
Author(s):  
Ernesto de la Rubia ◽  
Antonio Diaz-Estrella
Keyword(s):  
Virtual Reality ◽  
Gait Cycle ◽  
Inertial Sensors ◽  
Low Cost ◽  
Point Of View ◽  
Handheld Devices ◽  
Preliminary Evaluation ◽  
Virtual Reality System ◽  
Object Searching

Virtual reality has become a promising field in recent decades, and its potential now seems clearer than ever. With the development of handheld devices and wireless technologies, interest in virtual reality is also increasing. Therefore, there is an accompanying interest in inertial sensors, which can provide such advantages as small size and low cost. Such sensors can also operate wirelessly and be used in an increasing number of interactive applications. An example related to virtual reality is the ability to move naturally through virtual environments. This is the objective of the real-walking navigation technique, for which a number of advantages have previously been reported in terms of presence, object searching, and collision, among other concerns. In this article, we address the use of foot-mounted inertial sensors to achieve real-walking navigation in a wireless virtual reality system. First, an overall description of the problem is presented. Then, specific difficulties are identified, and a corresponding technique is proposed to overcome each: tracking of foot movements; determination of the user’s position; percentage estimation of the gait cycle, including oscillating movements of the head; stabilization of the velocity of the point of view; and synchronization of head and body yaw angles. Finally, a preliminary evaluation of the system is conducted in which data and comments from participants were collected.

Abnormalities Detection of IMU Based on PCA in Motion Monitoring

2012 ◽  
Vol 224 ◽  
pp. 533-538 ◽  
Author(s):  
Jing Zhou ◽  
Steven Su ◽  
Ai Huang Guo ◽  
Wei Dong Chen
Keyword(s):  
Measurement Method ◽  
Degrees Of Freedom ◽  
Inertial Sensors ◽  
Principal Component ◽  
Body Sensor Networks ◽  
Remote Measurement ◽  
Micro Electro Mechanical Systems ◽  
Inertial Measurement ◽  
Multiple Degrees Of Freedom ◽  
Measurement Units

Inertial measurement units (IMU) are used as an affordable and effective remote measurement method for health monitoring in body sensor networks (BSNs) based on tracking people’s daily motions and activities. These inertial sensors are mostly micro-electro-mechanical systems with a combination of multi-axis combinations of precision gyroscopes, accelerometers, and magnetometers to sense multiple degrees of freedom (DoF).Unfortunately in the process of motion monitoring actual sensor outputs may contain some abnormalities, which might result in the misinterpretations of activities. In this paper, we use Principal component analysis (PCA) combined with Hotelling’s T2 and SPE statistic to detect abnormal data in the process of motion monitoring with IMU to ensure the reliability and accuracy in application. The simulated results prove this method is effective and feasible.

Solvent-Based Polymer Swelling Characterization for the Development of the Nano/Micro-Particle Polymer Composite MEMS Corrosion Sensor

2014 ◽  
Author(s):  
Feng Pan ◽  
Abdoul Kader Maiga ◽  
Po-Hao Adam Huang
Keyword(s):  
Reaction Products ◽  
Material Transport ◽  
Sensing Element ◽  
Micro Electro Mechanical Systems ◽  
Polymer Swelling ◽  
Corrosion Sensor ◽  
Mems Technology ◽  
New Type ◽  
Oxide Removal

The concept of using Micro-Electro-Mechanical Systems (MEMS) for in-situ corrosion sensing and for long-term applications has been proposed and is currently under development by our research lab. This is a new type of sensing using MEMS technology and, to the knowledge of our team, has not been explored previously. The MEMS corrosion sensor is based on the oxidation of metal nano/micro-particle embedded in elastomeric polymer to form a composite sensing element. The polymer controls the diffusion into and out of the sensor while the corrosion of the metal particles inhibits electrical conduction which is used as the detection signal. The work presented here is based on part of the methods developed for the removal of native and process-induced metal oxides. A major aspect is the study of the swelling dynamics of the polymer matrix (polydimethylsiloxane, PDMS) intended for enhancing material transport of etchants into and reaction products out of the composite during oxide removal. More specifically, the characterization of the swelling of copper particles-PDMS composite samples in liquid solvent baths is presented.

Least square estimation-based adaptive complimentary filter for attitude estimation

2018 ◽  
Vol 41 (1) ◽  
pp. 235-245 ◽  
Author(s):  
Parag Narkhede ◽  
Alex Noel Joseph Raj ◽  
Vipan Kumar ◽  
Vinod Karar ◽  
Shashi Poddar
Keyword(s):  
Inertial Sensors ◽  
Low Cost ◽  
Attitude Estimation ◽  
Unmanned Vehicles ◽  
Least Square ◽  
Least Square Estimation ◽  
Micro Electro Mechanical Systems ◽  
Moving Vehicle ◽  
Complementary Filter ◽  
Filter Structure

Attitude estimation is one of the core fundamentals for navigation of unmanned vehicles and other robotic systems. With the advent of low cost and low accuracy micro-electro-mechanical systems (MEMS) based inertial sensors, these devices are used ubiquitously for all such commercial grade systems that need motion information. However, these sensors suffer from time-varying bias and noise parameters, which need to be compensated during system state estimation. Complementary filtering is one of such techniques that is used here for estimating attitude of a moving vehicle. However, the complementary filter structure is dependent on user fed gain parameters, KP and KI and needs a mechanism by which they can be obtained automatically. In this paper, an attempt has been made towards addressing this issue by applying least square estimation technique on the error obtained between estimated and measured attitude angles. The proposed algorithm simplifies the design of nonlinear complementary filter by computing the filter gains automatically. The experimental investigation has been carried out over several datasets, confirming the advantage of obtaining gain parameters automatically for the complementary filtering structure.

Automated Assembly and Hermetic Packaging of MOEMS for Applications Requiring Extended Shelf-Lives

2005 ◽  
Author(s):  
Dan O. Popa ◽  
Michael Deeds ◽  
Abiodun Fasoro ◽  
Heather Beardsley ◽  
Jeongsik Sin ◽  
...  
Keyword(s):  
Machine Vision ◽  
Shelf Life ◽  
Cost Effective ◽  
Wire Bonding ◽  
Automated Assembly ◽  
Hermetic Packaging ◽  
Die Attach ◽  
Pick And Place ◽  
Solder Reflow ◽  
Seam Sealing

In this paper we describe two modular automated microassembly systems, along with a several packaging processes that have been integrated to produce reliable and cost-effective MOEMS devices. The automated and packaging systems consists of robotics such as pick and place, insertion and fastening, machine vision and controls, and processes such as die attach, solder reflow by laser, wire bonding and seam sealing. The target MOEMS devices are intended for applications requiring a minimum twenty year shelf-life.

Tailoring of Stress Development in MEMS Packaging Systems

2002 ◽  
Vol 741 ◽  
Author(s):  
Satyajit S. Walwadkar ◽  
Junghyun Cho ◽  
P.W. Farrell ◽  
Lawrence E. Felton
Keyword(s):  
Microelectromechanical Systems ◽  
Inertial Sensors ◽  
Thermal Exposure ◽  
Origin And Evolution ◽  
Mems Packaging ◽  
Operation Conditions ◽  
Die Attach ◽  
Device Operation ◽  
Different Levels ◽  
Good Agreement

ABSTRACTA better understanding of the origin and evolution of the stresses is a crucial step in improving reliability of packaging systems for microelectromechanical systems (MEMS). Given its importance, we examine the stresses developed in hermetically packaged MEMS inertial sensors. For this purpose, an optical surface profilometer is employed to assess the stresses by measuring the curvature of dummy silicon dies (3.5×3.5 mm2) assembled in different types of packages and die attach adhesives. We also explore a temporal evolution of stresses during thermal exposure of the test packages in an effort to emulate actual packaging processes and device operation conditions. The result shows different levels of stresses generated from various adhesives and package types, and also a stress evolution during packaging processes. The mechanical stress data also show a good agreement with MEMS performance data obtained from actual accelerometers. Therefore, the stress data will not only be useful in better understanding performance of MEMS packages, but the testing protocol can also provide a diagnostic tool for very small packaging systems.

Novel MEMS Fabry-Perot Interferometric Pressure Sensors

2010 ◽  
Vol 638-642 ◽  
pp. 1009-1014 ◽  
Author(s):  
Ivan Padron ◽  
Anthony T. Fiory ◽  
Nuggehalli M. Ravindra
Keyword(s):  
Optical Fiber ◽  
Rigid Body ◽  
Pressure Sensors ◽  
Sensing Element ◽  
Micro Electro Mechanical Systems ◽  
Considerable Advantage ◽  
Fabry Perot ◽  
Mems Technology ◽  
Interferometric Sensor ◽  
Novel Design

A novel design for a Fabry-Perot Interferometric Sensor (FPIS) consisting of a Fabry-Perot cavity formed between two bonded surfaces is discussed. The Fabry-Perot cavity and the optical fiber to which it is coupled are used as the sensing element and interconnect, respectively. The Fabry-Perot cavity is fabricated using the Micro Electro Mechanical Systems (MEMS) technology. The introduction of a center rigid body diaphragm gives this sensor considerable advantage when compared with previous Fabry-Perot cavity based sensors.

Hermetic Packaging of Micro Scanner for Laser Display Applications

2005 ◽  
Author(s):  
Won Kyoung Choi ◽  
Moon Gi Cho ◽  
Sun Kyoung Seo ◽  
Hyuck Mo Lee ◽  
Byung Gil Jeong ◽  
...  
Keyword(s):  
Shear Strength ◽  
Good Adhesion ◽  
Raster Scanning ◽  
Hermetic Packaging ◽  
Laser Display ◽  
Hermetic Sealing ◽  
Experiment Method ◽  
Environmental Variations ◽  
Long Lifetime ◽  
Hermetic Package

Laser display technologies have been developed for an excellent expression of natural color, low power consumption and a long lifetime compared to other advanced displays, such as LCD, PDP and other projection type displays. The micro scanner is one of the key devices to make possible the raster scanning type laser projection displays. And the hermetic package of the micro scanner should be required for the protection from the environmental variations so as to keep the driving behavior uniform. Hermetic package can be ensured when the package is sealed hermetically without generating any outgases in the cavity. Thus, the hermetic sealing process was optimized through DOE (Design of Experiment) method using the Sn-In-Ag solder alloys instead of adhesives. And the characterizations of the packages were carried out in terms of hermeticity, shear strength, and interface microstructures. As a result, we’ve got about 2E−9 atm cc/sec He leak rate, which is low enough to pass the standard (MIL-STD-883E). Shear strength was as high as ∼80 MPa. The C-mode SAM images showed the continuous sealing area without any voids. In addition, the interfacial microstructures revealed good adhesion to the both parts, the glass lid and the ceramic package.

Preshaping Command Functions to Control the Dynamic Impacts in MEMS

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Aurelio Somà ◽  
Giorgio De Pasquale
Keyword(s):  
Impact Velocity ◽  
Vibration Amplitude ◽  
Control Method ◽  
Switching Time ◽  
Open Loop ◽  
Micro Electro Mechanical Systems ◽  
Electrostatically Actuated ◽  
Dynamic Performances ◽  
Device Lifetime ◽  
The Impact

The control of electrostatically actuated microsystems with open-loop strategies has the potential to reduce the switching time with immediate benefits on device performances and, on the other hand, to reduce the impact velocity between electrodes with benefits on the device lifetime and reliability. By applying to micro-electro-mechanical systems (MEMS) the controlled methods already validated on machines, it was demonstrated that the accuracy of the control is scalable with the dimensions. Residual vibrations of microstructures in the nanometer range are almost completely suppressed: they are reduced to 6% of the uncontrolled vibration amplitude. The reasons for implementing this kind of control are related to reliability enhancement, by reducing the impact velocity, and for the improvement of device dynamic performances. The robustness of the control method against errors in dynamic parameters evaluation was also demonstrated.

Sign in / Sign up

Export Citation Format

Share Document