Recent Submissions

  • Recent Progress on Flexible Capacitive Pressure Sensors: From Design and Materials to Applications

    Mishra, Rishabh B.; Elatab, Nazek; Hussain, Aftab M.; Hussain, Muhammad Mustafa (Advanced Materials Technologies, Wiley, 2021-03-05) [Article]
    For decades, the revolution in design and fabrication methodology of flexible capacitive pressure sensors using various inorganic/organic materials has significantly enhanced the field of flexible and wearable electronics with a wide range of applications in aerospace, automobiles, marine environment, robotics, healthcare, and consumer/portable electronics. Mathematical modelling, finite element simulations, and unique fabrication strategies are utilized to fabricate diverse shapes of diaphragms, shells, and cantilevers which function in normal, touch, or double touch modes, operation principles inspired from microelectromechanical systems (MEMS) based capacitive pressure sensing techniques. The capacitive pressure sensing technique detects changes in capacitance due to the deformation/deflection of a pressure sensitive mechanical element that alters the separation gap of the capacitor. Due to advancement in state-of-the-art fabrication technologies, the performance and properties of capacitive pressure sensors are enhanced. In this review paper, recent progress in flexible capacitive pressure sensing techniques in terms of design, materials, and fabrication strategies is reported. The mechanics and fabrication steps of paper-based low-cost MEMS/flexible devices are also broadly reported. Lastly, the applications of flexible capacitive pressure sensors, challenges, and future perspectives are discussed.
  • Acceleration Sensors: Sensing Mechanisms, Emerging Fabrication Strategies, Materials, and Applications

    Babatain, Wedyan; Bhattacharjee, Sumana; Hussain, Aftab M.; Hussain, Muhammad Mustafa (ACS Applied Electronic Materials, American Chemical Society (ACS), 2021-01-15) [Article]
    Accelerometers are among the most mature sensor technologies with a broad range of applications in multiple fields and industries. They represent the most widely used microelectromechanical system (MEMS) devices with excellent and reliable performance. MEMS acceleration sensors established dominance mainly in navigation and control applications. In recent years, however, recent technologies and materials have emerged that introduce novel sensing mechanisms, improve performance, enable customization, reduce cost, and reduce fabrication complexity. Herein, the recent advances in accelerometers based on MEMS and recent emerging technologies are reviewed. This work provides a comprehensive review of accelerometers’ sensing mechanisms and the main characteristics and features of each type of sensor, material, and fabrication strategies used to fabricate them. From the aspect of sensor application, this work focuses on reviewing applications that demonstrate the use of accelerometers manufactured using unconventional technologies and materials in prevailing fields such as healthcare monitoring, automotive industry, navigation, building, and structural monitoring. Moreover, challenges and future efforts needed to be addressed in this field are summarized.
  • Paper as a Substrate and an Active Material in Paper Electronics

    Khan, Sherjeel M.; Nassar, Joanna M.; Hussain, Muhammad Mustafa (ACS Applied Electronic Materials, American Chemical Society (ACS), 2020-11-16) [Article]
    Paper is an essential part of our daily life in many different ways. It is made by compressing cellulose fibers sourced from wood into thin sheets. Paper is an inherently flexible material which can transport liquids through its medium by capillary action without the need of external force. The mesh network of cellulose in paper gives it a unique set of mechanical properties. Owing to its exclusive and advantageous properties, paper is being used as an active material and a substrate in electronics. Paper as an active material means that paper is utilized in its intrinsic form without modifications. Activated (or functionalized) paper has been widely exploited in many applications, but in order to take true advantage of all the beneficial properties of paper, it needs to be used in its natural produced form. Notably, paper is employed in humidity sensors, pressure sensors, and MEMS devices in its natural form. Additionally, paper is used as a substrate in additively manufactured and origami-inspired electronic devices. Here, we present an overview of how paper is used to make fully flexible and low-cost devices. Furthermore, the emergence of paper-based point-of-care devices is briefly discussed.
  • Symmetrical orientation of spiral-interconnects for high mechanical stability of stretchable electronics

    Qaiser, Nadeem; Damdam, Asrar Nabil; Khan, Sherjeel Munsif; Hussain, Muhammad Mustafa (Institute of Electrical and Electronics Engineers (IEEE), 2020-10-30) [Conference Paper]
    Recently, interconnect based stretchable electronic devices have attained growing interest due to its application for various state-of-the-art technologies. Here, we report an engineered design of spiral interconnects for a series of stretchable networks referred to as the symmetrical series; wherein spirals connect to the island in the symmetry manner. A systematic analysis of Si-based spiral interconnects by numerical modeling, and experiments show that our design provides higher stretchability of 165% in comparison to the conventionally used nonsymmetrical design. The reason for high mechanical reliability is attributed to the favorable unwrapping profile of spiral interconnect due to the nature of forces acting on it during the stretching process. In contrast, for the nonsymmetrical series, the nature of tensile forces produces the rotation, and resultant tilting of spiral arm results in low stretchability of 150%. As a result, nonsymmetrical interconnect fails at earlier stages of stretching. Our study demonstrates the significance of the orientation of spiral interconnects linked to the island to attain the high performance of stretchable electronic devices.
  • Design Criteria for Horseshoe and Spiral-Based Interconnects for Highly Stretchable Electronic Devices

    Qaiser, Nadeem; Damdam, Asrar Nabil; Khan, Sherjeel Munsif; Bunaiyan, Saleh; Hussain, Muhammad Mustafa (Advanced Functional Materials, Wiley, 2020-10-27) [Article]
    Stretchable electronics can be used for numerous advanced applications such as soft and wearable actuators, sensors, bio-implantable devices, and surgical tools because of their ability to conform to curvilinear surfaces, including human skin. The efficacy of these devices depends on the development of stretchable geometries such as interconnection-based configurations and the associated mechanics that helps to achieve optimum configurations. This work presents the essential mechanics of silicon (Si) island-interconnection structures, which include horseshoe and spiral interconnections, without reducing the areal efficiency. In particular, this study demonstrates the range of the geometrical parameters where they have a high stretchability and cyclic life. The numerical results predict the areas that are prone to breaking followed by experimental validation. The figure-of-merit for these configurations is achieved by mapping the fracture-free zones for in-plane and out-of-plane stretching with essential implications in stretchable and wearable system design. Furthermore, this work demonstrates the mechanical response for a range of materials (i.e., copper, gold, aluminum, silver, and graphene) that experience the plastic deformations in contrast to conventionally used Si-based devices that represent the extended usage for advanced stretchable electronic devices. The detailed mechanics of these configurations provides comprehensive guidelines to manufacture wearable and stretchable electronic devices.
  • Mechanically flexible viscosity sensor for real-time monitoring of tubular architectures for industrial applications

    Nour, Maha A.; Khan, Sherjeel M.; Qaiser, Nadeem; Bunaiyan, Saleh A.; Hussain, Muhammad Mustafa (Engineering Reports, Wiley, 2020-10-25) [Article]
    Real-time monitoring of fluid viscosities in tubular systems is essential for industries transporting fluid media. The available real-time viscometers for tubular systems have major drawbacks, such as using invasive methods with large pressure drops due to flow disturbances, destructive installation processes with permanent tube damage, and limited operability with laminar flows. Therefore, developing a viscometer to address the above-mentioned concerns is required for industrial applications. In this study, a new application of a velocity-dependent viscometer using a novel design for real-time measurements with insignificant flow disruption is proposed. It involves a Poly (methyl-methacrylate) microchannel bridge with a microfluidic flowmeter attached to a mechanically flexible Polydimethylsiloxane platform connected to the inner surface of the pipe, which can adapt to different pipe diameters and curvatures. Moreover, the proposed viscometer uses the pipe flow driving force to flow fluids into the microchannel for measurement without requiring a pumping system or any sample withdrawals. The results of the simulation analysis match the experimental results of the sensor performance. The sensor can measure different viscosities in the range of 4-334 mPa s with a resolution higher than 2.7 mPa s. Finally, a stand-alone system is integrated with the sensor for wireless data transmission.
  • Stress concentration analysis and fabrication of silicon (100) based ultra-stretchable structures with parylene coating

    Rehman, Mutee Ur; Babatain, Wedyan; Shaikh, Sohail F.; Conchouso Gonzalez, David; Qaiser, Nadeem; Hussain, Muhammad Mustafa; Rojas, Jhonathan Prieto (Extreme Mechanics Letters, Elsevier BV, 2020-10-19) [Article]
    Research in stretchable electronics is helping to revolutionize the current electronic industry, particularly in wearable and bio-integrated devices. Cost-effectiveness and easy manufacturing are key factors that contribute to shaping the fate of such technologies. In this work, we present a fabrication method for a novel ultra-stretchable, serpentine-arm spiral (SAS) that was built using a low-cost, standard bulk silicon (100) wafer. However, structural defects that often appear during patterning processes, can lead to stress concentration and structural failure at these sites upon stretching. Parylene coating of the structures is proposed to minimize this stress concentration and improve structure's robustness. Finite element analysis (FEA) was performed to demonstrate the concentration of stress at these defective sites with 2 sizes (0.1μm and 1μm) and at different locations along the arms. Results show that SAS structures reach up to ∼80% stress reduction at the defective location compared to straight-arm spirals, while the parylene-coating helps to reduce it up to ∼60% further. On the other hand, fabricated uncoated, SAS structures reached up to ∼600% prescribed strain before fracture, while parylene-coating improves this maximum admissible strain in ∼50%. Additionally, a cyclic tensile test was then performed on the fabricated structures, uncoated and parylene-coated, for over 3000 cycles without fracture. The results observed on coated structures greatly improve the mechanical reliance of such brittle structures, which could be extended to other stretchable configurations.
  • Multi-Dimensional Integration and Packaging of Devices for Internet-of-Things Applications

    Elatab, Nazek; Suwaidan, Reema; Alghamdi, Yara; Alhazzany, Alhanouf; Almansour, Reema; Shaikh, Sohail F.; Khan, Sherjeel M.; Hussain, Muhammad Mustafa (Institute of Electrical and Electronics Engineers (IEEE), 2020-10-13) [Conference Paper]
    IoT applications are increasingly becoming widespread with more stringent system requirements. In this work, we demonstrate a nature-inspired integration and packaging technology that achieves self-powered multi-functional systems with optimized performance and small footprint area. The integration technique is based on bifacial usage of the substrate where devices on both sides are interconnected via through-substrate-vias. Multiple substrates are then integrated and folded into a 3D architecture using side-interlocks following a puzzle-like fashion. On the outer sides of the 3D architecture, sensors, RF devices and energy harvesters are integrated while on the inner faces, a solid-state battery in addition to power- management and data-management circuitry are embedded. To package the system, a polymeric encapsulant is used to protect the inner circuitry and enhance the mechanical resilience of the system. Finally, the system is used to send the collected data wirelessly to a phone using an embedded Bluetooth Low Energy unit.
  • Expandable Polymer Assisted Wearable Personalized Medicinal Platform

    Babatain, Wedyan; Gumus, Abdurrahman; Wicaksono, Irmandy; Buttner, Ulrich; Elatab, Nazek; Rehman, Mutee Ur; Qaiser, Nadeem; Conchouso Gonzalez, David; Hussain, Muhammad Mustafa (Advanced Materials Technologies, Wiley, 2020-09-09) [Article]
    Conventional healthcare, thoughts of treatment, and practice of medicine largely rely on the traditional concept of one size fits all. Personalized medicine is an emerging therapeutic approach that aims to develop a therapeutic technique that provides tailor-made therapy based on everyone’s individual needs by delivering the right drug at the right time with the right amount of dosage. Advancement in technologies such as wearable biosensors, point-of-care diagnostics, microfluidics, and artificial intelligence can enable the realization of effective personalized therapy. However, currently, there is a lack of a personalized minimally invasive wearable closed-loop drug delivery system that is continuous, automated, conformal to the skin, and cost-effective. Here, design, fabrication, optimization, and application of a personalized medicinal platform augmented with flexible biosensors, heaters, expandable actuator and processing units powered by a lightweight battery are shown. The platform provides precise drug delivery and preparation with spatiotemporal control over the administered dose as a response to real-time physiological changes of the individual. The system is conformal to the skin, and the drug is transdermally administered through an integrated microneedle. The developed platform is fabricated using rapid, cost-effective techniques that are independent of advanced microfabrication facilities to expand its applications to low-resource environments.
  • Soft Actuators for Soft Robotic Applications: A Review

    Elatab, Nazek; Mishra, Rishabh B.; Al-Modaf, Fhad; Joharji, Lana; Alsharif, Aljohara A.; Alamoudi, Haneen; Diaz, Marlon; Qaiser, Nadeem; Hussain, Muhammad Mustafa (Advanced Intelligent Systems, Wiley, 2020-08-23) [Article]
    Soft robotics technologies are paving the way toward robotic abilities which are vital for a wide range of applications, including manufacturing, manipulation, gripping, human–machine interaction, locomotion, and more. An essential component in a soft robot is the soft actuator which provides the system with a deformable body and allows it to interact with the environment to achieve a desired actuation pattern, such as locomotion. This Review article aims to provide researchers interested in the soft robotics field with a reference guide about the various state-of-the-art soft actuation methodologies that are developed with a wide range of stimuli including light, heat, applied electric and magnetic fields with a focus on their various applications in soft robotics. The underlying principles of the soft actuators are discussed with a focus on the resulting motion complexities, deformations, and multi-functionalities. Finally, various promising applications and examples of the different soft actuators are discussed in addition to their further development potential.
  • Multisensory graphene-skin for harsh-environment applications

    Shaikh, Sohail F.; Hussain, Muhammad Mustafa (Applied Physics Letters, AIP Publishing, 2020-08-17) [Article]
    Monitoring the environment using electronic systems in harsh environments requires materials and processes that can withstand harsh environments. Environmental harshness can come from the surrounding temperature, varying pressure, intense radiation, reactive chemicals, humidity, salinity, or a combination of any of these conditions. Here, we present graphene as a candidate for a multisensory flexible platform in harsh-environment applications. We designed sensors for harsh environments like high temperature (operating range up to 650 C), high salinity, and chemical harsh environments (pH sensing) on a single flexible polyimide sheet. The high-temperature graphene sensor gives a sensitivity of 260% higher than the Pt-based sensor. The temperature sensor acts between metal and a thermistor, thereby providing an opportunity to classify the region depending on temperature (<210 C linear and > 210 C up to 650 C as quadratic). Improved performances are observed for salinity and pH sensing in comparison with existing non-graphene solutions. The simple transfer free fabrication technique of graphene on a flexible platform and laser-induced graphene on a flexible polyimide sheet opens the potential for harsh-environment monitoring and multisensory graphene skin in future applications.
  • Flexible High-Efficiency Corrugated Monocrystalline Silicon Solar Cells for Application in Small Unmanned Aerial Vehicles for Payload Transportation

    Elatab, Nazek; Khan, Sherjeel M.; Hussain, Muhammad Mustafa (Energy Technology, Wiley, 2020-08-17) [Article]
    In recent years, small unmanned aerial vehicles (SUAVs) have proven to be exceptionally useful. However, most of the commercially available drones are electric powered and therefore have a short endurance. Solar powered UAVs have recently received increased attention due to their ability to fly continuously for several days using solar energy. For this purpose, solar cells must show high-efficiency, lightweight and ultra-flexibility in order to be fully compliant to the drone wings/body and avoid degrading its aerodynamic characteristics. Nevertheless, previous demonstrations used rigid/semi-flexible cells. Here, corrugated ultra-flexible silicon solar cells (19% efficiency) with a smaller specific weight (645 g/m2, encapsulated) are considered and used. A theoretical comparison between the performances of the corrugated vs. commercial semi-flexible cells is performed in terms of flight endurance in “AtlantikSolar” UAV. The results show that due to the ultra-lightweight of the corrugated cells and their ability to expand at higher temperatures without bowing, an enhancement in the flight time up to 19% can be achieved compared to the commercial cells which enables heavier payloads (7 lbs) transportation. Finally, the corrugated cells (12.5 cm by 4 cm) are experimentally tested on a small-sized drone under different conditions indoors and a 10% extended flight is reported.
  • Flexible and stretchable inorganic solar cells: Progress, challenges, and opportunities

    Elatab, Nazek; Hussain, Muhammad Mustafa (MRS Energy & Sustainability, Springer Nature, 2020-07-01) [Article]
    This review focuses on state-of-the-art research and development in the areas of flexible and stretchable inorganic solar cells, explains the principles behind the main technologies, highlights their key applications, and discusses future challenges. Flexible and stretchable solar cells have gained a growing attention in the last decade due to their ever-expanding range of applications from foldable electronics and robotics to wearables, transportation, and buildings. In this review, we discuss the different absorber and substrate materials in addition to the techniques that have been developed to achieve conformal and elastic inorganic solar cells which show improved efficiencies and enhanced reliabilities compared with their organic counterparts. The reviewed absorber materials range from thin films, including a-Si, copper indium gallium selenide, cadmium telluride, SiGe/III–V, and inorganic perovskite to low-dimensional and bulk materials. The development techniques are generally based on either the transfer-printing of thin cells onto various flexible substrates (e.g., metal foils, polymers, and thin glass) with or without shape engineering, the direct deposition of thin films on flexible substrates, or the etch-based corrugation technique applied on originally rigid cells. The advantages and disadvantages of each of these approaches are analyzed in terms of achieved efficiency, thermal and mechanical reliability, flexibility/stretchability, and economical sustainability.
  • Nature-inspired spherical silicon solar cell for three-dimensional light harvesting, improved dust and thermal management

    Elatab, Nazek; Qaiser, Nadeem; Babatain, Wedyan; Bahabry, Rabab; Shamsuddin, Rana; Hussain, Muhammad Mustafa (MRS Communications, Cambridge University Press (CUP), 2020-06-17) [Article]
    Unconventional techniques to benefit from the low-cost and high-efficiency monocrystalline silicon solar cells can lead to new device capabilities and engineering prospects. Here, a nature-inspired spherical solar cell is demonstrated, which is capable of capturing light three-dimensionally. The proposed cell architecture is based on monocrystalline silicon and is fabricated using a corrugation technique. The spherical cell shows an increase in power output by up to 101% with respect to a traditional flat cell with the same projection area using different reflective materials. Finally, the spherical cell shows advantages in terms of enhanced heat dissipation and reduced dust accumulation over conventional cells.
  • Low-cost foil/paper based touch mode pressure sensing element as artificial skin module for prosthetic hand

    Mishra, Rishabh B.; Khan, Sherjeel M.; Shaikh, Sohail F.; Hussain, Aftab M.; Hussain, Muhammad Mustafa (Institute of Electrical and Electronics Engineers (IEEE), 2020-06-15) [Conference Paper]
    Capacitive pressure sensors have several advantages in areas such as robotics, automation, aerospace, biomedical and consumer electronics. We present mathematical modelling, finite element analysis (FEA), fabrication and experimental characterization of ultra-low cost and paper-based, touch-mode, flexible capacitive pressure sensor element using Do-It-Yourself (DIY) technology. The pressure sensing element is utilized to design large-area electronics skin for low-cost prosthetic hands. The presented sensor is characterized in normal, transition, touch and saturation modes. The sensor has higher sensitivity and linearity in touch mode operation from 10 to 40 kPa of applied pressure compared to the normal (0 to 8 kPa), transition (8 to 10 kPa) and saturation mode (after 40 kPa) with response time of 15.85 ms. Advantages of the presented sensor are higher sensitivity, linear response, less diaphragm area, less von Mises stress at the clamped edges region, low temperature drift, robust structure and less separation gap for large pressure measurement compared to normal mode capacitive pressure sensors. The linear range of pressure change is utilized for controlling the position of a servo motor for precise movement in robotic arm using wireless communication, which can be utilized for designing skin-like structure for low-cost prosthetic hands.
  • Large-Scale Spherical Silicon Solar Cell for Advanced Light Management

    Elatab, Nazek; Qaiser, Nadeem; Bahabry, Rabab; Hussain, Muhammad Mustafa (Institute of Electrical and Electronics Engineers (IEEE), 2020-06-14) [Conference Paper]
    In order to realize a high power conversion efficiency, a solar cell should effectively utilize most of the incoming photons. Here, we demonstrate a spherical shaped solar cell that is capable of capturing direct, diffuse and background reflected light without the need for a mechanical sun-tracking tool. The spherical cell is based on monocrystalline silicon with an efficiency of 19% ad is developed using a corrugation technique to achieve flexibility in otherwise rigid silicon. The obtained spherical cell is large scale with a diameter of around 4 cm. Theoretical calculations in addition to experimental results confirm the merits of the spherical solar cell which shows an increase in instantaneous power output by 14.8% and 39.7% with respect to a traditional flat cell with the same ground area when sand and white paper are used as reflective background materials, respectively. Finally, the spherical shaped cell shows advantages in terms of lower dust accumulation rate due to its downward orientation.
  • Ultra-stretchable Silicon Solar Cells for Standalone Wearable and Foldable Electronics Application

    Elatab, Nazek; Qaiser, Nadeem; Bahabry, Rabab; Hussain, Muhammad Mustafa (Institute of Electrical and Electronics Engineers (IEEE), 2020-06-14) [Conference Paper]
    In order to achieve standalone wearable and foldable electronics, the integration of high efficiency stretchable energy harvesting devices is essential. Here, we demonstrate the development of ultra-stretchable solar cells based on monocrystalline silicon with interdigitated back contacts and high efficiency (19%). The stretchability of the photovoltaic devices is achieved by encapsulating the originally rigid solar cell with an elastomer followed by applying a deep-reactive ion etching based corrugation technique. Two different corrugation patterns are investigated: linear and triangular. The results show that, due to the ability of the triangular designs to relieve the generated strain, the cells can be stretched by up to twice their original size with no noticeable decline in the initial performance.
  • Textile electronics - Prospects, advances, challenges and opportunities

    Badghaish, Huda S.; Hussain, Muhammad Mustafa (MRS Advances, Cambridge University Press (CUP), 2020-05-29) [Article]
    The field of textile electronics aims to use clothing materials and fabrics as an active or activated substrate for electronics. This is an intriguing idea for researchers, however, the field comes with its own challenges and design requirements. A textile electronic system should be functional, reliable, safe and affordable while maintaining the original utility of the fabric. This review paper presents a comprehensive picture of prospects, advances, challenges and opportunities of textile electronics. It also offers a critical outlook to advance the field for technology translation.
  • Flexible Nanoporous Template for the Design and Development of Reusable Anti-COVID-19 Hydrophobic Face Masks

    Elatab, Nazek; Qaiser, Nadeem; Badghaish, Huda; Shaikh, Sohail F.; Hussain, Muhammad Mustafa (ACS Nano, American Chemical Society (ACS), 2020-05-20) [Article]
    Since the outbreak of the severe respiratory disease caused by the novel coronavirus (COVID-19), the use of face masks has become ubiquitous worldwide to control the rapid spread of this pandemic. As a result, the world is currently facing a face mask shortage, and some countries have placed limits on the number of masks that can be bought by each person. Although the surgical grade N95 mask provides the highest level of protection currently available, its filtration efficiency for sub-300 nm particles is around 85% due to its wider pore size (∼300 nm). Because the COVID-19 virus shows a diameter of around 65-125 nm, there is a need for developing more efficient masks. To overcome these issues, we demonstrate the development of a flexible, nanoporous membrane to achieve a reusable N95 mask with a replaceable membrane and enhanced filtration efficiency. We first developed a flexible nanoporous Si-based template on a silicon-on-insulator wafer using KOH etching and then used the template as a hard mask during a reactive ion etching process to transfer the patterns onto a flexible and lightweight (<0.12 g) polymeric membrane. Pores with sizes down to 5 nm were achieved with a narrow distribution. Theoretical calculations show that airflow rates above 85 L/min are possible through the mask, which confirms its breathability over a wide range of pore sizes, densities, membrane thicknesses, and pressure drops. Finally, the membrane is intrinsically hydrophobic, which contributes to antifouling and self-cleaning as a result of droplets rolling and sliding on the inclined mask area.
  • Metal coated polymer and paper-based cantilever design and analysis for acoustic pressure sensing

    Mishra, R. B.; Shaikh, Sohail F.; Hussain, Aftab M.; Hussain, Muhammad Mustafa (AIP Advances, AIP Publishing, 2020-05-12) [Article]
    Cantilevers are one of the most utilized mechanical elements for acoustic sensing. In comparison to the edge clamped diaphragms of different shapes, a single edge clamped cantilever makes an acoustic sensor mechanically sensitive for detection of lower pressure. The aspect ratio of cantilevers is one of the most important parameters which affect sensitivity. Herein, we present a mathematical, finite element method and experimental analysis to determine the effect of the aspect ratio on the resonant frequency, response time, mechanical sensitivity, and capacitive sensitivity of a cantilever-based acoustic pressure sensor. Three cantilevers of different aspect ratios (0.67, 1, and 1.5) have been chosen for sound pressure application to detect capacitance change. The cantilever with the smallest aspect ratio (0.67) has the highest response time (206 ms), mechanical sensitivity, and capacitive sensitivity (22 fF), which reduce after increasing the aspect ratio. The resonant frequency of the cantilever was also analyzed by applying sweep in sound frequency. It was found to be minimum for the cantilever with the smallest aspect ratio (510 Hz) and increases with an increase in the aspect ratio. We have applied the garage fabrication process using low cost, recyclable, and easily available materials such as metal coated polymer sheets, mounting tapes and glass slides as alternative materials for expensive materials.

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