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Dynamic Mechanical Characterizations of Thin Film Materials for Micro-Electro Mechanical Systems (PhD Thesis)

By: Material type: TextTextLanguage: English Publication details: Karachi : NED University of Engineering and Technology Department of Mechanical Engineering 2023Subject(s): DDC classification:
  • 621.381520378242 KHA
Online resources: Summary: Abstract I I The advancements in technology have led to the development of innovative concepts in micro-electro-mechanical systems (MEMS), including stretchable and flexible batteries and solar cells, electronic skins and wearable sensors, microactuators and positioning de, ices, foldable displays, etc. MEMS involves integrating mechanical and electronic systems on a micrometer scale, with thin films serving as the fundamental building blocks. These thin films, typically a few micrometers thick, can be deposited on compliant substrates to create stretchable and flexible MEMS devices, revolutionizing the field. In the realm of thin film research, the primary focus is largely experimental. Researchers have reported the extensive use of poly dimethyl siloxane (PDMS) as the only substrate material to form functional laminates using materials like Poly (3,4- ethylenedioxythiophene)polystyrene sulfonate (PEDOT:PSS), graphene, carbon nanotubes CNTs), silver nanoparticles (AgNPs), and nanowires (NWs). The mechanical characterizations of these laminates typically involve stretching and bending at very strain rates (-10-3 s-l ). However, there exists a notable gap in unveiling the more comprehensive and dynamic mechanical characterizations which include combined stretching and twisting, cyclic stretching and bending, and vibration testing. These advanced characterizations are vital to enhance device development as well as provide valuable insights into the performance and behaviour of these devices, thereby, leading to improved design and functionality. This research involves dynamic mechanical testing of various substrate-bonded thin films which includes PEDOT:PSS, PEDOT:PSS/Ag nanoplatelet films, and Poly(vinylidene fluoride) (PVDF)/ Silver Nano Particles (AgNPs), fabricated via a non¬vacuum-based rod-coating method on smooth, stretchable and flexible substrates. While designing new mechanical characterizations, an alternative, cost-effective material called Grey Room Temperature Vulcanizing (RTV), with mechanical properties similar to PDMS, was explored. The research has also encompassed a comprehensive analysis of the mechanical and material characteristics of RTV. The research results provide valuable insights into the dynamic mechanical behavior of PEDOT:PSS and its composites on RTV substrates and introduce an AgNPs-based PVDF/RTV laminate for piezoresistive MEMS sensor applications, offering potential advancements in stretchable, flexible, and twistable sensors, actuators, energy harvesting devices, and various other cutting-edge technologies.
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Item type Current library Shelving location Call number Status Date due Barcode
PHD Thesis PHD Thesis Reference Section Reference Section 621.381520378242 KHA Available 98664
PHD Thesis PHD Thesis Reference Section Reference Section 621.381520378242 KHA Available 98665

Abstract
I
I
The advancements in technology have led to the development of innovative concepts in micro-electro-mechanical systems (MEMS), including stretchable and flexible batteries and solar cells, electronic skins and wearable sensors, microactuators and positioning de, ices, foldable displays, etc. MEMS involves integrating mechanical and electronic systems on a micrometer scale, with thin films serving as the fundamental building blocks. These thin films, typically a few micrometers thick, can be deposited on compliant substrates to create stretchable and flexible MEMS devices, revolutionizing the field.
In the realm of thin film research, the primary focus is largely experimental.
Researchers have reported the extensive use of poly dimethyl siloxane (PDMS) as the only substrate material to form functional laminates using materials like Poly (3,4- ethylenedioxythiophene)polystyrene sulfonate (PEDOT:PSS), graphene, carbon nanotubes CNTs), silver nanoparticles (AgNPs), and nanowires (NWs). The mechanical characterizations of these laminates typically involve stretching and bending at very strain rates (-10-3 s-l ). However, there exists a notable gap in unveiling the more comprehensive and dynamic mechanical characterizations which include combined stretching and twisting, cyclic stretching and bending, and vibration testing. These advanced characterizations are vital to enhance device development as well as provide valuable insights into the performance and behaviour of these devices, thereby, leading to improved design and functionality.
This research involves dynamic mechanical testing of various substrate-bonded thin films which includes PEDOT:PSS, PEDOT:PSS/Ag nanoplatelet films, and Poly(vinylidene fluoride) (PVDF)/ Silver Nano Particles (AgNPs), fabricated via a non¬vacuum-based rod-coating method on smooth, stretchable and flexible substrates. While designing new mechanical characterizations, an alternative, cost-effective material called Grey Room Temperature Vulcanizing (RTV), with mechanical properties similar to PDMS, was explored. The research has also encompassed a comprehensive analysis of the mechanical and material characteristics of RTV. The research results provide valuable insights into the dynamic mechanical behavior of PEDOT:PSS and its composites on RTV substrates and introduce an AgNPs-based PVDF/RTV laminate for piezoresistive MEMS


sensor applications, offering potential advancements in stretchable, flexible, and twistable sensors, actuators, energy harvesting devices, and various other cutting-edge technologies.