PROGRESS REPORT
Project: Mechanical characterization of free-standing multilayered thin films
deposited by Physical Vapor Deposition (PVD)
OCTOBER 19, 2022
VAN NINH NGUYEN – N10166661
QUT Faculty of Engineering
1
Executive Summary
The development of thin film-based structures often requires thin films to be deposited onto substrate
via controllable and non-destructive transfer method. Comparing to normal materials, multilayered
films can achieve interesting combinations of strength, stiffness, and toughness. The mechanical
characterisation of thin films depends heavily on how they were developed. The thickness of thin
films can be varied from meters to millimetres or even micrometres and nanometres. Thin films
deposition is usually conducted on the existing surface of a bulk material via techniques varying from
atomic or molecular scale physics and chemistry. Here we report the progress of depositing
PMMA/Ti/TiO2 onto the glass substrate via a combination of techniques such as spin-coating and
Physical Vapor Deposition (PVD). The film was successfully deposited, however, the isolation effect
of the film with the surface has not been experimented yet. The report also includes management of
product quality, risk, ethical and sustainable practices during conducting the project.
2
Table of Contents
Executive Summary ................................................................................................................................ 1
List of Figures ......................................................................................................................................... 3
List of Tables .......................................................................................................................................... 3
1.
Introduction ..................................................................................................................................... 4
1.1.
Scope ....................................................................................................................................... 4
1.2.
Aim ......................................................................................................................................... 4
1.3.
Background ............................................................................................................................. 4
2.
Project Methodology ....................................................................................................................... 6
2.1.
Acquiring experimental materials and equipment .................................................................. 6
2.2.
Experimental Section .............................................................................................................. 7
2.2.1.
Preparation of PMMA coating ........................................................................................ 7
2.2.2.
Fabrication of PMMA/Ti/TiO2 film ................................................................................ 7
2.2.3.
Obtaining free-standing Ti/TiO2 film and investigating film properties ......................... 8
3.
Interim deliverables ........................................................................................................................ 9
4.
Risk and Limitations ....................................................................................................................... 9
5.
Quality........................................................................................................................................... 10
6.
Sustainability................................................................................................................................. 11
7.
Resources ...................................................................................................................................... 11
8.
Stakeholders .................................................................................................................................. 11
9.
Timeline and Deliverables ............................................................................................................ 11
10.
Conclusion and Recommendation ............................................................................................ 12
References ............................................................................................................................................. 14
Appendices............................................................................................................................................ 15
3
List of Figures
Figure 1. Schematic of Spic-coating method .......................................................................................... 4
Figure 2. Diagram of an electron beam vapor deposition chamber (image available at:
https://www.jeol.co.jp/en/science/eb.html) ............................................................................................. 5
Figure 3. PVD-75 .................................................................................................................................... 6
Figure 4. Spin coater ............................................................................................................................... 6
Figure 5. Deposition Chamber of PVD-75 ............................................................................................. 8
Figure 6. PMMA/Ti/TiO2 film on the glass substrate ............................................................................. 9
Figure 7. Cleansing Chamber and Contamination warning PVD-75 .................................................... 10
List of Tables
Table 1. Formula to spin-coating PMMA film (thickness 200nm) ......................................................... 7
Table 2. Setting for Ti/TiO2 deposition via PVD-75 .............................................................................. 8
Table 3. Setting for Ti/TiO2 deposition via PVD-75 .............................................................................. 8
Table 4. Timeline and Deliverables ...................................................................................................... 15
4
1. Introduction
1.1. Scope
As engineer practitioners, we regularly review and update on the progress of the on-going project
corresponding to the existed timeline, therefore, striving to derive engineering solutions to existing
community problems. The purpose of the report is to discuss what has been achieved for this project,
review any challenge or setback that we have been facing when conducting the project, and how these
were mitigated. Moreover, the report will propose any changes to the existing plans heading to the next
stage of the project. In this report, all interim variables will be introduced, following by reflection on
risk management and project decision making regarding to the ethical and sustainable aspect upon
project progress. Additionally, any relevant changes made to the project literature, methodology and
timelines are also included.
1.2. Aim
In this project, we are aiming to produce a nanoscale multi-layered free-standing film using Physical
Vapour Deposition method (PVD). The possibility to tailor the film properties through the variation of
the microstructure via PVD has allowed their entrance from the simplest protective coatings against
wear and corrosion, for example food packaging, home window, to the most technological complex
applications such as microelectronics and biomedicine [1].
1.3. Background
PVD methodology has many variations, i.e., vacuum evaporation, sputter deposition, arc vapor
deposition, ion plating, ion beam assisted deposition (IBAD) [2]. However, the project is only going to
cover the method of film deposition via a combination of spin coating and electron beam evaporation
(EBPVD).
Spin coating is not considered a PVD-type method but an effective method to deposit thin film onto flat
substrate. Usually, the substrate is placed on a flat plate of a machine called spin coater or spinner
(Figure 1) [3]. The substrate remains stable on the plate due to a suction force coming from a vacuum
chuck placed inside the machine. The substance chosen for the film is put in a suitable solvent and the
mixture in fluid form is uniformly applied on top of the substrate surface. The substrate is then rotated
at a speed up to 10000 RPM. Via this method, the film is coated by centrifugal force. The rotation is
continued until the fluid fully spread to all the edges of the substrate. The thickness of the film depends
majorly on the angular speed of the machine, the viscosity and concentration of the solution, and the
solvent [4]. The solvent applied in this method is usually volatile, and simultaneously evaporates.
Figure 1. Schematic of Spic-coating method
5
In a EBPVD process, the substrate is stabilized onto the surface of the substrate dome. The deposition
chamber must then be evacuated to a pressure of at least 0.01 Pa (7.5x10-5 Torr) to allow a passage for
the electrons from the electron gun to evaporate the material. These electrons form into an electron
beam accelerated to high kinetic energy. The kinetic energy is converted into other forms of energy,
including thermal energy, and heading towards the material used for deposition. These materials in form
of rods or ingots, are placed in the crucibles inside the chamber. The thermal energy heats up and
evaporates the material, causing it to sublimates. These vapor particles will be deposited to the substrate
via sputtering deposition. In this method, different materials can be deposited simultaneously, and the
desired thickness of the film can be manually controlled during the process. Schematic of the electron
beam physical vapor deposition chamber is shown in figure 2.
Figure 2. Diagram of an electron beam vapor deposition chamber (image available at:
https://www.jeol.co.jp/en/science/eb.html)
To obtain a free-standing multilayer film, the film must be able to be separated from the substrate
surface. Therefore, it is important to assess the interaction of the materials used for deposition and the
solvent used to create isolation effect. Acetone is considered to be a highly effective solvent to
dissolve PMMA [5]. On the other hand, it was also found that acetone significantly enhanced the
adherence property and provided a smooth surface of TiO2 film while exerting less effect on the
crystal structure of either TiO2 or Ti [6].
6
2. Project Methodology
The project plan and methodology has been discussed and agreed between the supervisors and the
student engineer. As previously planned, the project will be conducted in two semesters. The project
operation is based mainly in QUT’s Faculty of Engineering Facility. The project is divided into three
stages.
2.1. Acquiring experimental materials and equipment
The initial stage of the project is focusing on the acquiring the necessary materials and chemicals and
sufficient machinery and any measuring apparatus and setting up the lab for the film deposition. The
final thin film design including film structure and thickness will be proposed by the student engineer.
It is verified and confirmed by the supervisor. However, while conducting the project, any changes
made to the design will be recorded by both parties.
For this project, the chosen material is Poly(methyl methacrylate) (PMMA), Titanium (Ti), Titanium
Dioxide (TiO2). The chemical related to this project includes anisole, acetone, and tetrahydrofuran
(THF). The experiment equipment used are PVD-75 (Figure 3), spin coater (Figure 4).
Figure 3. PVD-75
Figure 4. Spin coater
7
2.2. Experimental Section
During the second stage, the film deposition will be conducted in the facilities provided by the QUT
school of School of Chemistry and Physics under the monitoring and supervision of both the project
supervisors, lab instructors and the student engineer. The progress of the project is recorded by the
student engineer to the project supervisor to make any necessary adjustments to current project plan.
Any shortage or errors regarding material or equipment are to be noticed immediately by the student
engineer and the supervisor to produce the solutions to the problems. The film deposition stage is
divided into several minor phases.
2.2.1. Preparation of PMMA coating
The first phase is to employ PMMA layer on top of the substrate before depositing the film. This layer
function as an “protection” layer, isolating the thin film and the substrate upon interacting with the
solvent. The PMMA solution was prepared by mixing PMMA powder with anisole with a ratio of
40mg:1ml. The mixture was stirred for 15 minutes and filtered using 0.22 µm syringe filter. For the
substrates, we used glass specimens with dimensions 25mm x 25mm x 1mm. The substrate was
prepared by cleansing in mixture of acetone-ethanol and 2-propanol in 20 minutes and then UV-ozone
treated for 9 minutes. After cleansing was done, the glass substrate was placed inside the spin coater. A
PMMA film was synthesized by using a syringe injecting the PMMA solution evenly onto the glass
surface. The spin coater was set using the setting shown in table 1.
Table 1. Formula to spin-coating PMMA film (thickness 200nm)
Step
Spin speed (RPM)
Time (s)
Acceleration (RPM/s)
1
1000
20
500
2
3600
40
800
After the rotation was finished, the coated surface was cleaned using a nitrogen blower to remove
unevaporated solvent and unreacted particles. The substrate is then cured under the heat of 160o for 45 minutes.
2.2.2. Fabrication of PMMA/Ti/TiO2 film
The second step is to employ the multilayer thin film using PVD-75 via the electron beam vapor
deposition sputtering configuration. Firstly, the PC vent was started to remove the air inside the
chamber. Ti and TiO2 ingots were placed inside the crucibles inside the PVD-75 chamber (figure 5).
The prepared glass substrates coated with PMMA were stabilized onto the substrate dome. After that,
the PVD-75 was initiated using the setting shown in table 2 and table 3.
8
Figure 5. Deposition Chamber of PVD-75
Table 2. Setting for Ti/TiO2 deposition via PVD-75
Layer
Material
Ti
TiO2
Pre-Condition
Deposition Thickness Ramp1
rate (Å/s)
(kÅ)
Pwr (%)
5
1
4
2
10
10
Ramp1
Time
(s)
Soak1
Time
(s)
Ramp2
Pwr (%)
Ramp2
Time
(s)
Soak2
Time
(s)
60
120
10
60
17
22
120
120
10
60
Table 3. Setting for Ti/TiO2 deposition via PVD-75
Post Condition
Material
Ti
TiO2
Source/Sensor
Feed
Pwr (%)
Ramp
Time
(s)
Feed
Time
(s)
Idle
Power
(%)
Ramp
time (s)
Max.
Power
(%)
Slew
Rate
(%)
0
0
180
180
0
0
0
0
5
0
75
50
100
100
2.2.3. Obtaining free-standing Ti/TiO2 film and investigating film properties
Finally, the synthesis of the substrate and the film will be put through a solvent to separate the substrate,
the PMMA layer, and the film. Upon the separation of the film and the substrate, the film can be
obtained using a TEM grid.
The final stage of the project includes investigating the microstructure of the film using Scanning
Electron Microscope (SEM) and testing the mechanical properties of the obtained thin film. The test
conducted on the thin film includes tensile strength, yield strength, elasticity, nanomechanical
properties via nanoindentation technique. Nanoindentation technique employs high resolution sensors
and actuators to continuously control and monitor the loads and displacements on a nanometer-sized
indenter relative to the sample’s surface. And from the load-displacement data, Hardness and Young’s
modulus of the material can be obtained.
9
3. Interim deliverables
The final conceptual design for the film parameters were approved by the supervisors. There were three
layers of materials deposited onto the glass substrates (Figure 6). The thickness of the PMMA, Ti and
TiO2 layers were 200 nm, 400 nm, and 200 nm, respectively.
Figure 6. PMMA/Ti/TiO2 film on the glass substrate
4. Risk and Limitations
Most of the project operation was conducted in QUT’s facility. Therefore, all parties involved in the
project must followed the QUT safety induction rule. All possible hazards must be identified before
depositing the film using PVD-75 or monitoring the measuring equipment (Figure 7). Heavy materials
and all hazardous chemicals and solvents must be handled carefully. Sufficiently knowledge of the
chemicals is required before conducting lab experiments. Therefore, all operations of student engineer
must be monitored and closely supervised by either the lab instructor or supervisor. Protective gears
such as lab goggles, lab coats, and enclosed shoes or lab boots must be always worn in lab. All lab
instructions and equipment’s manual must always be followed by the supervisors and student engineer.
The only limitation of this project was the possible lack of necessary equipment, materials, or chemicals.
Therefore, the supervisors had proposed to conduct the project in different lab or facilities if that ever
happens.
10
Figure 7. Cleansing Chamber and Contamination warning PVD-75
5. Quality
The quality of the project based on the management of multiple independent factors. Predictions and
actual outcomes differ because quality will often change during implementation. For this project,
success can be predicted through the management of the reliability of information from literature
review, time allocations for different stages of the project and the correct practice of proposed
methodology. For example, all specimens must not be handled with bare hands but with lab tongs. The
substrate must always be cleansed and pay close attention. The depositing of PMMA solvent must be
evenly spread across the glass substrate to avoid bubbles or unevenly deposition of the film. The settings
for the EBPVD must be investigated to produce consistent layers of film. Testing and investigating on
different samples should be conducted to ensure the consistency of the results. To ensure the expected
outcome of the project is achieved, any progress made must be reported by the student engineer to the
supervisors on a weekly basis. Fortnightly meetings are conducted to discuss and introduce any
suggestions that can be made to improve the current result of the project. The more professional practice
of the three concepts, the greater the quality and validity of the solutions.
11
6. Sustainability
For this project, both short-term and long-term impact will be focused. Short-term impact was the
deposition the thin multilayered film with the proposed list of materials and the interaction between the
film and the substrate. Long-term goal is to focus on how to improve the film characteristics and the
substrate effect isolation.
Furthermore, impact on environment of this project were also investigated. The impact of this project
to the environment is closely related to the risk management of the project. For example, all interactions
with hazardous chemicals by the student engineer must be monitored by the lab instructor. Disposal of
any residue materials or chemicals must followed guidelines and rules stated by the Queensland
Government. All lab activities were exercised inside QUT facilities to avoid noise pollution to the
surroundings. Lastly, life cycle assessment (LCA) must be conducted on the final product studying the
environmental and social cost of raw materials involved in this project, transport, manufacturing, use
and disposal [7].
7. Resources
The resources used in this project consist of those involved and assisting in the project's planning,
experimenting, and testing which are further outlined in the Stakeholders section. The materials and
chemicals are provided by QUT synthesis lab. Machines for testing are provided by QUT School of
Mechanical, Medical and Process Engineering facility. Work safety regulations from the QUT safety
must also be followed. This section is clearly outlined in the Risks and Limitations.
8. Stakeholders
According to the project’s plan, shareholders will participate in an important role including two main
supervisors, a student engineer, lab supervisors, and instructors. Two main supervisors are Professor
Mohamad Mirkhalaf Alazani and Dr. Tuquabo Tesfamichael who will be primarily responsible for the
project “Mechanical characterisation of free-standing multilayered thin films deposited by Physical
Vapor Deposition (PVD)”. The student engineer responsible for this project is Van Ninh Nguyen
(studying unit EGH400-1 in Bachelor of Engineering). In addition, the synthesis lab facility for this
project is allowed by Professor Hongxia Wang. There is Associate Professor Wayde Martens and lab
intructors Michael who were helping to investigate and develop the project.
9. Timeline and Deliverables
The timeline, deliverables, dependency, and time allocations each section were clearly identified in
table 1 in appendix A.
12
10. Conclusion and Recommendation
The initial experiments were conducted to deposited PMMA, Ti, and TiO2 layer onto the glass
substrate, respectively. Previous research indicates that PMMA can be dissolved easily in acetone or
THF chemical suggesting that there is a high chance to acquire a free-standing multilayered film of
Ti/TiO2. However, further experiments on the isolation effect of the film with the PMMA layer from
the glass will be conducted to verify this possibility. If the obtained film fails to isolate from the
substrate, it is recommended to reassess the thickness of each layer of the current film or choose a
stronger base solvent for the experiment. On the other hand, there are more tests on the mechanical
properties and nanostructure of the film which will be investigated further in the following phase of
the project.
13
14
References
[1] Koetter, R. (2021) Common PVD applications VaporTech, VaporTech. Available at:
https://vaportech.com/blog-common-pvdapplications/#:~:text=Thin%2Dfilm%20deposition%20technologies%2C%20like,production%20of%
20microelectronics%20and%20sensors. (Accessed: October 28, 2022).
[2] D.M. Mattox, “Physical Vapor Deposition (PVD) processes”, Metal Finishing, 100 (2002), pp.
394-408, available at:
[3] Cohen, Edward; Lightfoot, E. J. (2011), "Coating Processes", Kirk-Othmer Encyclopedia of
Chemical Technology, New York: John
Wiley, doi:10.1002/0471238961.1921182203150805.a01.pub3, ISBN 9780471238966
[4] Scriven, L. E. (1988). "Physics and Applications of DIP Coating and Spin Coating". MRS
Proceedings. Cambridge University Press (CUP). 121: 717. doi:10.1557/proc-121-717. ISSN 19464274
[5] Zhou, X.D., Zhang, S.C., Huebner, W. et al. Effect of the solvent on the particle morphology of
spray dried PMMA. Journal of Materials Science 36, 3759–3768 (2001).
https://doi.org/10.1023/A:1017982018651
[6] P. Kajitvichyanukul, S. Pongpom, A. Watcharenwong, J. Ananpatattarachai, “Effect of Acetyl
Acetone on Property of TiO2 Thin film for Photocatalytic of Chromium(VI) from Aqueous Solution”,
CMU. Journal Special Issue on Nanotechnology (2005) Vol. 4(1), p. 87-93
[7] R. Watts, S. Harrington, D. Cruickshanks-Boyd, G. Davies, A. Piani, L. Harland, D. Rice,
“Implementing Sustainability: Principles and Practice”, Engineers Australia, Engineers Australia (EA)
Sustainability Committee, (2015). ISSN: 978-1-922107-55-B
15
Appendices
Appendix A
Table 4. Timeline and Deliverables
Number
Focus
Deliverable
Dependency
Release
Date/
Milestone
1
Literature
Review
Literature Review
Report included in Project
Proposal
3 (student
engineer and
supervisors)
Due:
07/09/2022
2
Work
performance 1
Evidence of your development as
a Professional Engineer, through
professional conduct in the
management of your project.
1
Due:
07/09/2022
3
Project Design/
Preparation
Confirmed final designs/final
structures, prepare the list of
materials and equipment
5 (student
engineer,
supervisors,
and project
counsellors)
Due:
26/10/2022
4
Project progress
report
Written Report and Oral
Presentation – update any risks or
outcome (quality) changes from
the project proposal
1
Due:
26/10/2022
5
Work
performance 2
Evidence of your development as
a Professional Engineer, through
professional conduct in the
management of your project.
1
Due: Week
2-7
(Semester 1
of 2023)
6
Modelling/ Rapid
prototype &
experiment
Start stage 1-2-3 stated in
methodology section
5 (student
engineer,
supervisors,
and project
counsellors)
Due: Week
2-7
(Semester 1
of 2023)
7
Experiment and
Testing
Conduct tests and experiment on
the final product for data
5 (student
engineer,
supervisors,
and project
counsellors)
Due: Week
2-7
(Semester 1
of 2023)
8
Work
performance 3
Evidence of your development as
a Professional Engineer, through
professional conduct in the
management of your project.
1
Due: Week
2-7
(Semester 1
of 2023)
9
Test & Validate/
Verify
Improve the model and conduct
further testing on more samples to
5 (student
engineer,
supervisors,
Due: Week
8-11
16
10
Draft report
11
Stakeholder
consultation
12
Project Delivery
Report & Oral
Defence
improve the consistency of the
result
and project
counsellors)
(Semester 1
of 2023)
The draft report of the final
project report & oral defence for
supervisors to check
1
Due: Week
11-12
(Semester 1
of 2023)
5 (student
engineer,
supervisors,
and project
counsellors)
Due: Week
11-12
(Semester 1
of 2023)
1
Due: end of
semester 1
of 2023
Final Report