Ali Javey (Advisor)

Research Advised by Professor Ali Javey

Javey Group:  List of Projects | List of Researchers

BPNX1031: Scalable Infrared Photodetectors based on Large-Grain Tellurium Film

Hyong Min Kim
Naoki Higashitarumizu
2025

Tellurium is a narrow-gap, p-type semiconductor with promising potential for future electronic and optoelectronic devices. Te’s band gap can be tuned from 0.31 eV in bulk form to 1.04 eV in monolayer form. Unlike many other competing 2D semiconductors, Te is air-stable and can be deposited on a substrate of choice by thermal evaporation or solution synthesis. Photodetectors based on solution-synthesized Te nanoflakes have already been demonstrated, with specific detectivity in near-IR at or above 10^9 Jones. However, solution-synthesis of Te nanoflakes is not scalable, and...

BPNX1023: CMOS-Compatible Doping of 2D Semiconductors

Inha Kim
Naoki Higashitarumizu
2025

2D materials are among the most promising candidates for next-generation semiconductor devices due to their exceptional electronic transport properties and composition of a single atomic layer, which offers significant advantages for integration density. However, high contact resistance and challenges in doping present obstacles to their practical applications. In this work, we aim to explore various methods to overcome these issues and achieve technological breakthroughs that will enable these materials to become integral components in a wide range of applications.

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BPNX1011: Nanoscale Electronics with Tellurium

I K M Reaz Rahman
Naoki Higashitarumizu
Taehoon Kim
2025

Tellurium has a one-dimensional atomic structure that favors anisotropic electronic properties. Thermally evaporated tellurium has intrigued renewed interest in nanoscale electronics due to its near ambient crystallization, featuring single crystal orientation in micro-sized domain. Here we aim to study the performance limits of tellurium thin film transistors as we scale them to single grain domains. This will allow us to test the performance limits of tellurium transistors and pave the way for its viability for integration with standard silicon processes.

Project...

BPNX1006: Quantitative Optical Characterization of Indium Selenide

Jamie Geng
2024

Bulk gamma-InSe has a direct bandgap of 1.24 eV, which corresponds to near infrared (NIR) wavelengths (λ = 1.0 µm) useful in optoelectronic applications from biometric detectors to silicon photonics. However, its potential for optoelectronic applications is largely untapped due in part to the lack of quantitative studies of its optical properties. Here, we study the unusually low absorptance and high photoluminescence quantum efficiency of single-crystalline InSe flakes with thickness in the hundreds of nanometers. InSe emits brightly at room temperature from its direct bandgap with a peak...

BPN971: Mechanically Flexible Mid-Wave Infrared Imagers using Black Phosphorus Ink Films

Theodorus Jonathan Wijaya
Naoki Higashitarumizu
Shu Wang
Hyong Min Kim
Dehui Zhang
Kyuho Lee
Shogo Tajima
Shifan Wang
2025

Midwave infrared (MWIR) is significant for applications such as sensing, imaging, and spectroscopy. Traditional materials in this wavelength range, III-V and II-VI semiconductors, has poor performance due to their high Auger recombination rate and large dark currents. Due to the better properties of black phosphorus (BP) such as its low Auger recombination coefficient, BP-based mid-infrared light emitters and detectors have shown to outperform the state-of-the-art commercial devices. However, the scalability of these devices remains questionable because of the limitations of...

Hyong Min Kim

Graduate Student Researcher
Electrical Engineering and Computer Sciences
Professor Ali Javey (Advisor)
Ph.D. 2028 (Anticipated)

Hyong is a Ph.D. student in the Electrical Engineering and Computer Sciences Department at University of California, Berkeley. He received his Bachelor's Degree in Electrical Engineering from the Univeristy of Pennsylvania in 2023. In his undergraduate research, Hyong studied quantum emission from strained 2D materials, ferroelectric field-emission transistors based on AlScN/2D material heterostructures, and scanning probe characterization of 1D-2D material interfaces. Hyong's current research at Berkeley is on fabricating next-generation Mid-Wave Infrared (MWIR) optoelectronic devices...

BPN999: Wearable Sweat Sensors with High-Throughput Fabrication

Noelle Davis
Pooja Mehta
Amanda King
Seung-Rok Kim
Yullim Lee
Nicole Qing
2025

We have been developing sweat sensors to analyze physiological and metabolic health information, such as sweat rate, glucose levels, pH, and various electrolytes, from any surface on the body surface where sweat glands are present. However, the stiff sweat sensors developed so far struggle to detect subtle signal changes, especially on soft skin. This is due to a mechanical mismatch between the rigid sweat sensor and the pliable skin, which can lead to motion artifacts and delamination of the patch from skin. Specifically, the stiff sensor cannot easily stretch along with the...

Nicole Qing

Undergraduate Researcher
Electrical Engineering and Computer Sciences
Professor Ali Javey (Advisor)
B.S. 2024

Seung-Rok Kim

Postdoctoral Researcher
Electrical Engineering and Computer Sciences
Professor Ali Javey (Advisor)

Seung-Rok Kim is a postdoctoral research associate in Electrical Engineering and Computer Sciences at the University of California, Berkeley, a postdoctoral researcher at Berkeley Sensor & Actuator Center (BSAC), and a research affiliate in the Materials Science Division at Lawrence Berkeley National Laboratory with a joint appointment. He received a Ph.D. in Materials Science and Engineering from Yonsei University in 2021, and was a postdoctoral research associate and research professor at Yonsei University in 2021 and 2023. Seung-Rok Kim then joined Javey...

Dehui Zhang

Postdoctoral Researcher
Electrical Engineering and Computer Sciences
Professor Ali Javey (Advisor)

Dehui Zhang is a postdoctoral researcher in Electrical Electrical Engineering and Computer Sciences at the University of California, Berkeley, a postdoctoral researcher at Berkeley Sensor & Actuator Center (BSAC), and a research affiliate in the Materials Science Division at Lawrence Berkeley National Laboratory. He received a Ph.D. in Electrical and Computer Engineering from University of Michigan, Ann Arbor in 2021, and was a postdoctoral researcher at University of California, Los Angeles in 2021-2023. Dehui Zhang joined Javey Research Group in September 2023...