ADVANCED TRANSPARENT CONDUCTIVE OXIDE (IZO / ZnO / ZTO)

TCO PROCESS DEVELOPMENT

Developed and optimized transparent conductive oxide thin films for adaptive electro-optical devices through solution-processed fabrication, thermal annealing, and electrical performance engineering. The project focused on achieving high optical transparency, controlled sheet resistance, improved film uniformity, and stable voltage propagation characteristics required for next-generation photonic and electronic devices

Thin FilmsTCOIZOZnOZTOProcess DevelopmentAnnealingElectrical CharacterizationMaterials EngineeringYield Optimization

>95%Optical transmittance target

>100 MOhm to kOhmResistance improvement direction

IZO / ZnO / ZTOMaterial system

Engineering Challenge

Transparent electrodes for liquid crystal devices must simultaneously provide low electrical resistance, high optical transmittance, and stable manufacturing performance. Early electrode structures exhibited conductivity limitations and significant process-to-process variation, making device performance inconsistent.

Process Development & Optimization

I investigated multilayer IZO/ZnO/ZTO architectures, optimized spin-coating and deposition conditions, and developed reduced-oxygen thermal annealing processes to improve carrier transport within the films. Electrical and optical characterization data were used to establish relationships between film structure, conductivity, and transparency while identifying a stable process window for repeatable fabrication.

Results & Impact

The optimized process significantly improved electrical conductivity while preserving excellent optical transmission. The work established a more robust transparent-electrode platform for liquid crystal devices and demonstrated practical experience in thin-film engineering, process optimization, materials characterization, and data-driven process development.

Skills Demonstrated

Thin-Film Process Development, Materials Engineering, Thermal Processing, Electrical Characterization, Optical Metrology, Process Optimization, Root Cause Analysis, Process Integration

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ZTO Modal Layer • Voltage Gradient Control • Low-Frequency AC Operation

Modal LC Lens Development Via Voltage Gradient Engineering

Developed electrically tunable liquid crystal modal lenses using engineered Zinc Tin Oxide (ZTO) resistive layers to generate controlled voltage gradients for adaptive focal tuning. The project combined thin-film engineering, electrical characterization, and device integration to improve lens performance and stability.

LC LensMicroholeVoltage GradientDevice Integration

2DFocal-shift behavior

50%Architecture complexity reduction

Single electrodeDevice concept

Modal LC Lens Development Via Voltage Gradient Engineering

Engineering Challenge

Generating a stable lateral voltage gradient across a liquid crystal aperture is critical for focal tuning but is highly sensitive to resistive-layer uniformity, electrical transport behavior, and fabrication variability. Early devices showed focal instability and inconsistent electro-optical response.

Process Development

To improve performance, I optimized precursor preparation, spin-coating parameters, modal-layer thickness, and thermal annealing conditions. Electrical measurements and focal-length characterization were used to correlate thin-film properties with device behavior and identify the primary causes of voltage-distribution instability.

Results & Impact

The optimized process enabled more uniform voltage propagation, improved focal tuning repeatability, and enhanced electro-optical response stability. This work demonstrated how semiconductor thin-film engineering can directly influence electric-field control and adaptive device performance.

Skills Demonstrated

Process Development, Thin-Film Engineering, Electrical Metrology, Device Integration, Failure Analysis, Thermal Processing, Electro-Optical Characterization

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Liquid Crystal Engineering • Polarization Control - VVB / OAM Generation

Polarization Conversion and Vector Vortex Beam Generator array

Designed and optimized liquid crystal photonic devices capable of converting uniform polarization states into spatially varying polarization distributions for vector vortex beam generation and advanced wavefront engineering applications.

LC ArrayPolarizationVVBOAMOptical Alignment

Alignment-freeFabrication approach

Multi-beamConversion capability

l = +/-2OAM state range

Polarization Conversion and Vector Vortex Beam Generator array

Engineering Challenge

The generation of high-quality vector vortex beams requires precise control of liquid crystal alignment, phase retardation, and polarization conversion across the entire device aperture. Small fabrication variations can significantly degrade beam quality and conversion efficiency.

Process Development

I optimized liquid crystal alignment procedures, cell assembly processes, and operating conditions to improve phase uniformity and polarization conversion performance. Experimental characterization was used to identify sources of optical non-uniformity and guide iterative process improvements.

Results & Impact

The optimized devices achieved improved polarization conversion performance, enhanced beam quality, and more consistent operation. The project strengthened expertise in device fabrication, optical metrology, process control, and experimental validation.

Skills Demonstrated

Device Fabrication, Process Characterization, Optical Metrology, Process Optimization, Advanced Materials Engineering, Experimental Validation

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Multifocal Microlenses • Microstructured Electrodes

Stacked LC Microstructure Speckle Suppression

Contributed as a co-author to the development and characterization of multifocal liquid crystal microlens devices designed to reduce laser speckle in projection systems through dynamically controlled optical modulation.

LC DeviceSpeckle ReductionOptics LettersMetrology

67.4%Speckle contrast reduction

Optics LettersPublication venue

Stacked LCDevice architecture

Stacked LC Microstructure Speckle Suppression

Engineering Challenge

Laser projection systems suffer from coherence-induced speckle noise that reduces image quality. Developing an effective speckle-reduction solution required careful optimization of microlens behavior, electric-field distribution, and device operating conditions.

Process Development

I participated in device fabrication, electro-optical testing, and performance characterization activities. Experimental data were used to evaluate multifocal operation, optimize driving conditions, and validate the effectiveness of the device architecture for speckle suppression.

Results & Impact

The developed system demonstrated significant speckle reduction capability while maintaining optical performance. The work contributed to a peer-reviewed publication and strengthened expertise in device validation, characterization, and advanced electro-optical system development.

Skills Demonstrated

Device Integration, Process Validation, Electro-Optical Characterization, Experimental Testing, Performance Optimization, Engineering Analysis