Photovoltaic Scientist

[jeffw]

Send inquiries to jeffrey.worth at gmail.com


Career Objective: A senior level / director position involving
materials engineering in alternative energy and/or innovative nano/
micro-technology. Examples: materials synthesis - processes –
characterization - production with applications in solar cells
(material properties, device physics, process optimization), solid
state micro-circuit devices, thin films, thick films, synthetic
diamond, microelectronic packaging, fuel cell technology.


Professional Summary


Director / Senior Scientist-Engineer: Solar Cell Technology, Thin /
Thick Films, Materials Synthesis
A highly motivated, results-oriented, and creative individual with 20
years of diversified experience and documented contributions in
advanced technology involving electronic materials synthesis and
fabrication. Expertise includes knowledge and hands-on experience of
thin and thick film technology, microelectronic packaging, materials
analysis and electrical characterization, vacuum equipment and
deposition processes (PVD, CVD), high-temperature processing,
metallization (vacuum, electroplating, spraying, metal-ceramic
bonding), optical filters, joining-brazing-soldering assembly, wet
powder spraying, sintering, electron microscopy, process-properties-
microstructure relationships, crystallization processes,
crystallographic characterization-relationships, electronic
materials / devices / sensors, photovoltaics, hydrogen separation for
fuel cells, thermal management materials and techniques, magnetic
sensors, photography, imaging.



General Qualifications

• Problem Solving Skills: Thrive on complex problems through
analysis; conscientious, resourceful, adaptive, creative thinker with
attention to detail, quality, and global perspective; computer
analysis, simulation, and visualization for reporting results.
• Communication Skills: Routine reports in JMP and Powerpoint; strong
interpersonal skills; interact and communicate with individuals on all
levels from the establishment of customer rapport to management and
mentoring.
• Product Development, Project Management, Applications Eng., R&D:
Advance and develop company products and capabilities through strong
interactive teamwork within the company, and with associated companies
and customers.
• Advisory / Management Experience: Supervise engineers, technicians,
operators, and provide engineering support / advise production.
• Marketing Experience: Showcase technical products and performance
via presentations, publications, posters, conferences, and trade
shows; work closely with sales.







Professional Experience


xxxxxxxxxxx Chatsworth, CA DIRECTOR of RESEARCH 1/2/08 -Research
and Advisory Support
• Conducting research on novel methods of thin film silicon deposition
via non-aqueous electro-deposition leading to production on flexible
plastic substrates: comprehensive literature reviews in silicon
electro-deposition and related technologies, such as ionic liquids and
batteries; designed lab layout and coordinated facilities engineering
for class 10,000 clean room (Servicor) with state-of-the art nitrogen/
argon dry box (Vac-Atm) for electrochemical research; ordered clean
room, specified dry box design, and selected auxiliary equipment; met
with industry pros on organosilicon chemistry and industrial scale non-
aqueous electroplating manufacturing; completed ECS course in
electrochemical measurements; establish university consultants.
• Supporting the materials processing and characterization aspects of
rice hull-to-silicon refining process methodology to UMG level at
factory scale: stages of pulverization, pyrolysis, chemical treatment,
carbo-thermal reduction; manage impurity measurements by ICP-MS and
LECO of rice hull and rice hull ash at various process stages for
purification effectiveness, analyze experimental data with JMP and
compare to literature; investigate silica technology (fumed vs.
precipitated) related to silicon refining; met with ICP-MS vendors to
select analytical equipment for factory installation at international
sites for process monitoring of silicon refining factory and other
analytical tools for bulk silicon measurements.









Noribachi LLC, Albuquerque, NM PHOTOVOLTAIC APPLICATION CONSULTANT
12/07 Development Engineering – Novel Solar Cell Applications in
Consumer Markets
• Photovoltaic devices – novel concepts for consumer markets; filed 2
patent applications.
Ronald
Petkie
Page 2/4


Advent Solar, Albuquerque, NM PROCESS INTEGRATION
ENGINEER 8/06 – 9/07 Engineering Group - Supporting High
Volume Production – 5, 6 inch Silicon
EWT Cell Technology
• Partnered with company statistician for daily monitoring and
analysis of EWT cell yield / efficiency issues
and corrective action; established metrology protocols performed
silicon wafer processing DOEs and statistical analysis (JMP) of
results to find or validate improvements in solar cell processing
techniques compared to baseline process.
• Developed methods and performed measurements of electrical,
physical, and chemical properties to monitor, evaluate, and improve
production processes, cell performance, and device physics for process
integration: relationships between Light I-V, Suns Voc, AR nitride
reflectance, IQE, and lifetime (Semilab), resistive components, EL,
FLIR, ICP-MS, double diode I-V modeling, established the critical
importance of silicon quality on cell performance; served to connect
and introduce ideas between R&D and Engineering groups; supported
micro-analytical needs in the company through sample preparation
techniques, interaction with SEM / EDX at local lab, and FMEA by
materials characterization.
• Designed, measured, and analyzed resistive test structures using
baseline production processes to characterize various components of
series resistance and lifetime in EWT solar cells, especially contact
resistance; evaluated 0.7 ohm-cm silicon material and cell performance
to baseline wafer resistivity.
• Evaluated quality of silicon wafers from various suppliers through
electrical, physical, and chemical
(ICP-MS) properties analysis of source material and cell performance
by production line DOEs;
implemented silicon recycling program for cost savings.






Evergreen Solar, Marlboro, MA PROCESS CHARACTERIZATION
ENGINEER 2005 - 2006
Technical Staff in R&D Crystal Growth - String Ribbon Silicon Wafers
Conventional Cell Technology
• Developed strategies for investigating and correlating process
parameters with physical properties of silicon wafers, solar cell
components, and other materials throughout R&D and Manufacturing for
fabrication process improvements; FMEA by materials characterization.
• Increased ICP-MS limit of detection for trace metal impurities by
10x for silicon pellets, crucible melts, wafers, and solar cells
through sample preparation; developed and maintained comprehensive ICP-
MS database for research and quality; SEM/EDS analysis of process
variations using metallography and chemical etching sample preparation
techniques; utilized numerous materials characterization techniques:
FE-SEM, Auger, ESCA, microscopy (IR, polarized light, acoustical), Pb-
free solder joint analysis, microwave photoconductivity (lifetime),
FTIR, DART, EBSD, IR photo-elasticity (residual stress for crack
detection), XRD; published weekly technical reports on materials
characterization results; purchased JEOL 6490LV SEM.
• Fabricated novel thick film aluminum (p+) ohmic back contacts to
silicon solar cells via wet powder spray (aerosol via airbrush) and
swirl coat deposition (Asymtek); correlated physical properties of
thick films with cell performance.
• Predicted transient behavior of metal contamination in silicon
wafers during crystal growth by mathematical modeling, as derived from
first principles, of manufacturing data through observations of
lifetime behavior in string ribbon silicon wafers; determined
effective segregation coefficients by ICP-MS, compared with model; JMP
software basics.





First Solar, Perrysburg, OH CONTRACT MATERIALS ENGINEER
1/05 – 4/05
Senior Materials Engineer in Development Group
Thin Film Cell Technology
• Designed process, performed fabrication, and tested cell performance
of screen printed or non-aqueous wet powder spray deposited, thick
film graphite-based pastes on thin film CdTe/CdS test structures for
feasibility study of improved back contact by doped thick films.






Power and Energy, Inc., Ivyland, PA SENIOR MATERIALS
ENGINEER 2003 - 2004
Principal Investigator, Fuel Cells R&D, Hydrogen Separator Fabrication
• Designed and fabricated prototype hydrogen gas separators by
deposition of nanoparticle metal alloy powders and hybrid deposition
techniques in thin and thick films, such as multi-layered thin film
alloys (PVD), screen printing, wet powder spray technology, high-
temperature processing, isostatic pressing; set-up fabrication lab;
directed engineer;
• Awarded co-filed patent 7,125,440 for high permeance hydrogen
separation technology for fuel cells; reviewed latest advances in
hydrogen separation technology for fuel cells; assisted in writing
grant proposals and progress reports.
Ronald Petkie

Page 3/4

• Characterized product membranes for failure mode by XPS and Auger;
measured gas permeance by electro-mechanical computerized control of
flow and pressure using LabView with DAQ boards and custom gas
fixtures.

Diamonex, Allentown, PA SENIOR ENGINEER / SCIENTIST 1996 – 2002
Principal Investigator - CVD Diamond - Advanced Metallization and
Microelectronic Packaging
• Applications engineering, R&D prototyping, and marketing of CVD
diamond for thermal management: development and assembly of
microelectronic packages by novel attachment schemes for incorporating
CVD diamond submounts into customer-specified, high- performance
applications. Assisted / taught customers in application of diamond
submounts in package design. Cost analysis. Project reporting to
funding agencies (DARPA, NSA) and customers.
• Major Accomplishments: Awarded 4 patents related to hands-on
product development of diamond submounts and micro-electronic
packaging involving thermal management: Robust, brazeable
metallization (PVD) technology applied to rf transistor
communications, patent 6,531,226; Microstructure-controlled mechanical
properties of thick film metal on diamond for high-temperature
applications, patent 6,830,780; First thick film resistor (also with
very low TCR) on diamond for communications circuits, patent
6,723,420; Diamond submount for CPUs, patent PCT/US02/01436; Others -
Fabricated diamond-based dual high power transformer core using MCM-
like laminate structure with nine-levels of electrically
interconnected patterned diamond wafers by electroplated thick film
copper on diamond and Pb-free solder BGA; metal-ceramic bonding and
packaging (Cu, Ag, Au clad diamond) for GaAs packaging applications.
• Created, coordinated, and maintained separate prototyping lab for
materials processing and microelectronic packaging; development of
electronic materials by thin (PVD) and thick film technology; directed
engineers / technicians. Attracted significant development and
production revenue through technical presentations and reports.
• Engineered equipment and implemented custom product fabrication in
CVD diamond wafer processing: photomask design, laser machining,
characterized vacuum deposition system for DC magnetron metallization
with rf biasing, photolithography, etching, electroplating of copper
and silver, high temperature processing, plasma processing, via hole
technology, multilayer registration; hot filament CVD diamond growth,
substrate lapping, mechanical / chemical polishing, mechanical design.
Materials characterization and analysis: metrology, SEM, EDS,
profilometry, microstructure, adhesion, hardness, resistivity,
defects.
• Developed and applied joining/ bonding technology to diamond
substrates for brazing, soldering, thermal stress and compliance for
thick metal films on diamond and other ceramics, planarization, phase
diagram engineering, active brazing alloys, assembly,
manufacturability, technology transfer. Provided engineering support:
development of improvements and standard operating procedures for all
aspects of CVD diamond production and assisted other groups.

GE Corporate R&D Center, NY THIN FILMS ENGINEER 1996 – 1996
Contract Assignment (through employment agency) - Principal
Investigator
Dielectrics and Coatings Group, Thin Film Synthesis and Optical
Characterization
• Successfully designed and fabricated rugate filters for laser band
stops with AR coating on plexiglass by characterization / optimization
of low-temperature Plasma Enhanced Chemical Vapor Deposition (PE-CVD)
process for multilayered silicon oxy-nitride thin films on plexiglass
and oxidized silicon.
• Engineered equipment / Programmed processes in Visual Basic for
filter design and computer interface (DAQ board) for real-time,
electro-mechanical control of deposition process in PECVD system;
measured and characterized film properties as a function of process
parameters: ellipsometry, spectrophotometry, adhesion, profilometry.
• Contributed the bulk of laboratory development work that resulted in
issued patent for rugate optical filters for GE R&D

RPI, Troy, NY Ph.D. STUDENT 1990 - 1995
Materials Characterization Scientist, Rensselaer Polytechnic Institute
Materials Eng. Dept., Electron Microscopy Laboratory
• Introduced electron back-scattered diffraction (EBSD) coupled to
Rodrigues-Frank space analysis for crystallographic characterization
into the department; produced thesis in crystallographic
characterization of microstructure; wrote extensive code in Visual
Basic for the analysis and visualization.
• Characterized metals and alloys: scanning and transmission electron
microscopy, EDS, EBSD, XRD, prepared samples for electron microscopy:
metallography, etching, bonding, wire saw, dimpling, ion milling,
electro-polishing; maintained semiconductor clean room: constructed
and repaired fabrication equipment.
• IBM Fellowship: 1 year
Ronald Petkie

Page 4/4

IBM Research, Yorktown Heights, NY SENIOR ASSOCIATE
ENGINEER 1986-1990
Thin Film Fabrication Engineer - Materials Laboratory in Central
Scientific Services
• Engineered equipment / designed and implemented physical vapor
deposition (PVD) techniques and processes (dual e-beam, rf sputtering
with bias, ion beam assisted evaporation) to obtain desired film and
properties via process optimization and computer-controlled electro-
mechanical systems: multilayer films, ceramics, intermediates,
compounds, amorphous and precise metal alloys, ion source operation,
reactive evaporation and sputtering, reactive thin solid films, self-
propagating high-temperature synthesis (explosive crystallization),
etc.
• Characterized electrical, chemical, mechanical, and microstructural
properties using RBS, EDS, SEM, optical microscopy, ellipsometry, film
metrology, resistivity, stress measurements, x-ray diffraction, etc.
• Collaborated with scientists and provided technical expertise in
research community for the development and fabrication of novel thin
film structures using a variety of PVD fabrication techniques.
• Designed and built circuits for electro-mechanical control; vacuum
system maintenance.



IBM, Research Triangle Park, NC SENIOR ASSOCIATE ENGINEER
1982 – 1986
Manufacturing & Process Development Engineer - Magnetic Wand and
Holographic Engineering
• Served as manufacturing and equipment engineer: Coordinated and
supervised low-volume wafer processing production line (several
technicians) in clean room laboratory, including photolithography,
electroplating, physical vapor deposition (PVD permalloy by e-beam
within magnetic field, rf induction, thermal), and sputtering (etching
and deposition) for over 100,000 magnetic sensor chips based on
permalloy / sapphire magneto-resistive sensors.
• Maintained quality control and high yield through statistical
process control (SPC) of material properties: film metrology,
resistive and magnetic characteristics, defect monitoring with
corrective action, etc.



PSU, University Park, PA M.S. STUDENT 1979 - 1981
Electrical Engineer, Pennsylvania State University
Electrical Engineering Dept., Solid State Device Laboratory
• Focused coursework towards solid state semiconductor physics, device
design, and photovoltaics; produced thesis on The Electrical
Characterization of RF-sputtered Thin Film CdTe for Photovoltaic
Applications; designed and fabricated photovoltaic device test
structures; optimized sputtering process and metallization in
conjunction with Materials Research Laboratory.
• Characterized electrical and photovoltaic device performance and
physics by designing and building environmental test chambers.
Designed and built electronic circuits for current-voltage (dark,
light), capacitance-voltage-frequency, Hall effect (carrier typing),
resistivity.


Education
Ph.D. Materials Engineering, Rensselaer Polytechnic Institute, Troy,
NY
Emphasis: electronic materials, materials characterization
M.S. Electrical Engineering, Pennsylvania State University, University
Park, PA
Emphasis: photovoltaics, semiconductors physics, devices, electrical
characterization
B.S. Physics, Pennsylvania State University, University Park, PA

Publications
Patents Issued: 5 total - 4 issued in US, 1 issued in Europe
• 3 as single author in thin films and thick films (metal-ceramic
bonding)
• 1 co-authored patent in hydrogen separation through nano-particles.
• 1 co-authored in CVD diamond packaging

Patents Pending – Recent: 2 in photovoltaic applications

Technical Publications: 32