JACK CHUNG

Senior Research Scientist

KLA, Milpitas, CA

​06/2022 - present

 

• DUV/VUV optical coatings and photodetectors

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Postdoctoral Scholar

NSEC, UC Berkeley, Berkeley, CA

​07/2018 - 05/2022

 

• Combined material design, nanofabrication, and electronic measurement to investigate the electrical and thermoelectric properties of electronic states in moiré materials (which are twisted 2D materials).

• Performed magneto-optical (MCD and MOKE) and magnetoresistance measurements to study 2D materials.

• Designed and built a sample holder for an attoDRY cryogenic system. With 2X electrical connections at a time multiple devices can be mounted.

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Graduate Research Assistant

Purdue University, West Lafayette, IN

​2010 - 2017

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• Designed and fabricated twisted bilayer graphene (tBLG) devices to investigate the effects of rotational misalignment (leading to energy band hybridization) on their electrical properties. Conducted electrical measurements under variable temperatures (0.3 K to 300 K) and magnetic fields.

• Fabricated and characterized graphene phototransistors on undoped silicon carbide semiconducting substrates. Achieved position-sensitive photoresponse (> 100 um from the graphene device) with a responsivity of ~10 A/W. Also investigated graphene-CdSe nanoparticle devices for photodetection.

 

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• Designed and built 2 CVD systems with electronic gas flow controls for graphene grown on a copper substrate. Developed and optimized recipes for high reproducibility and high-quality graphene films (with sub-millimeter domain size and field-effect mobility of 3k-6k cm^2/(V s)).

• Developed growth recipes for single-crystalline tBLG grains. Characterized the low-energy Raman modes of tBLG and discovered new interlayer lattice vibrations.

• Led the development of an electrolytic gating method to control the optical and vibrational properties in tBLG. Obtained a maximum 6-fold Raman intensity modulation.

• Assembled and characterized 2D heterostructures consisting of graphene and tungsten disulfide (2D semiconductor) for photodetector and photovoltaic applications. Demonstrated broadband enhancement in photocarrier generation and Raman scattering intensity.

• Served as a graduate teaching assistant for several undergraduate level classes (including modern mechanics, electric & magnetic interactions, and general physics) for 10 semesters. Conducted recitation sessions (< 40 students/class) for problem-solving and led laboratory classes.

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Engineer (R&D)

Compass Technology Company Ltd., Hong Kong

​03/2008 - 03/2009

 

• Conducted reliability analyses on flexible printed circuit boards received from customers and company production lines.

• Interacted with process engineers with feedback to optimize prototype development procedures.