Surface Patterning of BioCompatible Polymers Using EUV Lasers - - PowerPoint PPT Presentation
Surface Patterning of BioCompatible Polymers Using EUV Lasers Using EUV Lasers By Ammar Al Beruti and Turki Mahrous Colorado State University Senior Project Fall 2010 Outline Project Main Idea Previous Work Preview Why
By Ammar Al Beruti and Turki Mahrous Colorado State University Senior Project – Fall 2010
Project Main Idea Previous Work Preview Why Biocompatible Polymers? Project Description Conclusions and Future Work Budget Questions?
Developing a methodology to produce nanoscale structures using biocompatible polymers Using the effects of EUV lasers illumination (interference) (interference)
Nanolithography Techniques: 1) Electron Beam Lithography 2) Focused Ion Beam Lithography 3) Colloidal Lithography 4) EUV Lithography
* Picture taken from www.psiltd.co.uk Electron Beam
What is Unique About EUV? HighEnergy Radiation Short Wavelength (46.9 nm)
Description of the EUV Laser
Description of the EUV Laser
Applications: Medical Implantation HighSensitivity Biosensors Tissue Engineering
Tissue engineered heart valve
* Picture taken from http://en.wikipedia.org/wiki/Tissue_engineering
Research and Experimentation in Biopolymers Tested 20 different biopolymers Recommended Tecoflex SG80A Tried different concentrations Concluded that biopolymers react to EUV radiation
Tecoflex SG80A
Experiment
EUV Mask Polymer Substrate Polymer Substrate Preparing Photoresist Analysis Exposure Sample Coating 3 2 1 4
Experiment 1) Preparing the Photoresist (0.83% Concentration) Used Pro Explorer Balance to weigh the polymer (100 mg of Tecoflex SG80A)
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(100 mg of Tecoflex SG80A)
Experiment 1) Preparing the Photoresist (0.83% Concentration) Used a 1000micron pipette to measure the desired amount of solvent (12 mL of THF)
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desired amount of solvent (12 mL of THF)
Experiment 1) Preparing the Photoresist (0.83% Concentration) Used the Sonic Bath method to dissolve the polymer in the solvent
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polymer in the solvent
Experiment 2) Preparing and Coating Samples Cleave the Silicon wafer
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Experiment 2) Preparing and Coating Samples Clean the samples using Methanol and Acetone
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Experiment 2) Preparing and Coating Samples Use the Spin Coater to coat the samples
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Experiment 2) Preparing and Coating Samples Use the Hot Plate to bake the coated samples
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Experiment 2) Preparing and Coating Samples Attach the coated sample to the sample holder
2 Nickel Mesh Mask Metal Grip
Experiment 3) Sample Exposure to EUV Laser Place the sample holder in the chamber
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the chamber Evacuate the chamber Expose the sample
Experiment 4) Analyzing the Exposed Sample Microscope Atomic Force Microscopy (AFM)
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Results 1) First Sample Scratches on the surface of the sample Couldn’t see the pattern Needed to repeat the experiment
Results
AFM Scan of Sample 1
Results 2) Second Sample Pattern was clear Poor Quality (Contaminated) Had to debug the error and repeat the experiment
Results
AFM Scan of Sample 2
Results 3) Third Sample Pattern is visible Surface roughness Granularity
Results
AFM Scan of Sample 3
Results
AFM Scan of Sample 3
Conclusions Proved that Tecoflex SG80A can be patterned Proved that the methodology is effective Contamination Photoresist is not stable
Goals for Next Semester 1) Determining the penetration depth 2) Obtaining a very thin homogeneous layer of polymers
1) Follow extra clean conditions 2) Explore different ways to mix the solution 3) Testing different spin coating protocols
4 $20 Oring (for laser) 1 $2 Plastic Syringes 5 $20 Glass Syringe 1 $8 Syringe Filters 6 $18 Syringe Filters 6 $18 TEM Grids (Meshes) 1 $30 AFM (Per Hour) 1 hour $60 Masks 2 $10 Gloves 1 box $7 Methanol 1 $25 Acetone 1 $20 Compressed Nitrogen 1 $160 Total $380
* All expenses were covered by the ERC facility and the Chemistry Department at Colorado State University