Macquarie University: Flexible Sensor Materials - CDR Career Episode 3

This report, a Competency Demonstration Report (CDR) Career Episode 3, details a project focused on the material aspect of flexible sensors, undertaken at Macquarie University. The project aimed to design and develop flexible sensors incorporating materials suitable for bending, stretching, and resh...Read More

Competency Demonstration Report (CDR)
Career Episode 3

1.0 Career Episode- 3
1.1 Introduction
Project Name: - Material aspect of Flexible Sensors.
Location of the Project: - Macquarie University, Sydney, Australia.
Duration of the project: - [Please fill].
Organization: - Macquarie University.
Position within Project: - Masters of Engineering (Electronics Engineering Major)
postgraduate student.
1.2 Background
1.2.1 Characteristics of the Project
This project revolves around the fact that flexible sensors can be built using a number of
materials that have been identified to be effortlessly applied to that of soft as well as differently
shaped surfaces like that of human skin or might as well be textile fabrics. This project
particularly deals with the designing and development of flexible sensors with appropriate usage
of innovation along with their integration into variously existing systems. This project also puts
forward the current state belonging to the flexible sensors along with the particular impact of the
same upon the materials belonging to the same field of development.
1.2.2 Objective of the Project
The primary objective related to this project is to design and develop flexible sensors that
will have the inclusion of aspects similar to that of materials carrying the potential to be folded
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and then implemented into the various systems for application. In addition to this, the primary
objective of this project is to design and develop sensors that will have the inclusion of
functionalities like bending, fabrication as well as stretch ability. The development of flexible
sensors will have the application of the same into various flexible devices in regards to the
increase of digitalization around the world.
1.2.3 My work area
I was assigned with a number of responsibilities by the team leader along with the other
individuals that belonged to the same team as well. I had typically divided the materials into
various groups in accordance to the common role that belonged to each of the material playing a
part within the flexible sensor. Following this, I had presented the different kinds of substrates as
well as made a discussion regarding their thermal stability, surface quality, stretchability as well
as transparency.
1.2.4 Organization chart
Figure-1: Chronology of the Organization
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1.2.5 My responsibilities
I had carried out the following responsibilities during the entire time for which the project
was carried out,
 I had divided the materials that will be integrated within the flexible sensors based on
their common role that each of the material carried.
 I had highlighted the properties of conductivity along with transparency for the
conductive materials while I had taken into consideration the functions of mobility as
well as stability for the semiconductor materials.
 I had chosen the metals, which carry the properties in larger amounts to be integrated into
the flexible sensors putting forward a better performance when implemented within
different systems for application.
 I had carried out the usage of metals into differently existing geometries such as the like
of nanowires, liquefied conductors as well as nanoparticles to fulfil the particular
requirements of flexibility and transparency.
 I have also made use of organic conductors that consists of conductive properties, which
are commonly referred to as electrically conductive polymers (ECP).
1.3 Personal Engineering Activity
1.3.1 Theory of Project
I had proposed a plan for the designing and developing of sensors that can be
implemented and installed into various systems for application that will have the added potential
of being stretched, bended and reshaped according to the needs. I have considered a number of
materials that have the potential existence of properties in relation to conductivity such as metals,
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semiconductors, dielectrics as well as organic conductors. I have divided each of the material
individually on the basis of what they are capable of and how they can help towards a better
working of the flexible sensor. With the help of all these materials having the suitable properties,
I have developed and designed a number of sensors for different purposes such as strain sensors,
pressure sensors and temperature detectors.
1.3.2 Engineering knowledge and application of skills in the Project
I have properly identified the various types of materials that can be properly implemented
and given rise to such flexible sensors that will carry the special properties of being stretched,
bended as well as reshaped according to the needs of individuals. I have made proper utilization
of metals, metal oxides, organic materials as well as silicon nanomembranes that can be a part of
such flexible sensors as different materials helping to serve the purpose it is meant for. I have
made use of copper (Cu), silver (Ag), molybdenum (Mo), platinum (Pt), chromium (Cr),
aluminum (Al), nickel (Ni) as well as magnesium (Mg) to be used for the development due to
higher presence of electrical conductivity and higher rate of mechanical stability. I have made
use of Au in the thin-film of metallic contact as a reason of its resistance towards oxidation. The
under layers of this structure have been built using Titanium or Cr for the increasing of adhesion
to that of the substrate. I had identified the potential carrier mobility of Carbon along with its
specific ability to sustain the conduction of high currents and made use of it to develop the thin
film within the transistors, electrodes for the battery as well as the sensors to be built. I have also
made use of CNT fibers for the flexible sensors because of its containment of lower levels of
resistivities that will help for a better and efficient working of the flexible sensors. In addition to
this, I have utilized organic conductors because of their properties such as electrical, optical as
well as magnetic close to the metals in the flexible sensors.
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Figure-1: Flexible Sensor
Figure-2: List of Flexible Sensors
1.3.3 Tasks performed by me
I had been assigned by multiple activities for the designing and the developing of these
flexible sensors. These are,
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 I had identified a number of materials belonging to different types that can be used for the
designing of flexible sensors like that of the metals, semiconductors, dielectrics, as well
as organic conductors.
 I had fabricated various devices on larger sized substrates in order to create thin as well
as ultra-flexible systems including sensors that can be folded without having to alter the
functionality belonging to them.
 I had chosen metals for the flexible sensors taking into account the conductivity as well
as the transparency of the same.
 I had made use of semiconductors in reference to their properties such as the field effect
of mobility along with that of stability.
 Lastly, I had considered the usage of dielectrics into the designing and developing of the
flexible sensors depending upon their dielectric constant as well as the breakdown
voltage of different dielectrics that will help in better performance of the flexible sensors.
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Figure-3: Flexible Devices
1.3.4 Issues identified and mitigated
Issues
 Initially I had made use of only metals for the entire design of the flexible sensors but
landed up with the fact that metals do not show such properties of flexibility under
normal conditions.
 I had properly made a design of a single type of sensor with the implementation of a
number of materials on the basis of their particular properties but identified a number of
issues.
Mitigation
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 With the issue that I had identified with the help of only using metals, I considered the
usage of semiconductors, dielectrics as well as organic conductors along with metals for a
better performance.
 I had identified and developed a number of different sensors with the use of same
materials such as pressure, temperature and strain sensors.
1.3.5 Collaborated work
I had properly worked and carried out the responsibilities assigned to me by the team
leader and I had worked efficiently with diligence along with my team members to put forward
the best possible design for the flexible sensor. The developed product was efficiently working
and fulfilling the initial objectives of the project with the help of a successful collaboration.
1.4 Summary
1.4.1 Overview of the Project
The entire project was to design as well as develop flexible sensors with the help of a
number of materials that included the likes of metals, semiconductors, dielectrics as well as
organic conductors. These flexible sensors will have the provision to be installed and
implemented within differently existing systems that will lead to better results and will serve the
purpose of sensing pressure, temperature as well as strain collectively.
1.4.2 Meeting of the goals
The objectives in accordance to the project that had been initially placed forward was to
build sensors that will have the additional properties of bending, stretching as well as getting
reshaped depending upon the need. In accordance to the project that I had undertaken, the
sensors should have the potential ability to sense pressure, temperature and strain that was a
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complete success as the end result of the entire project was a developed sensor that was flexible
having the properties of different materials and serving different purposes.
1.4.3 Personal Contribution
I had primarily worked towards the choosing of all the materials that will be specifically
utilized for the developing of these flexible sensors along with the amount of raw materials that
is needed for this purpose to be specific. I had carried out other activities such as choosing the
specific metals, semiconductors, dielectrics as well as organic conductors that will be used
within the designing and developing of this flexible sensors. As a result, I ad efficiently carried
out all of the responsibilities that had been entrusted upon me by the team leader.
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