Ali Javey (Advisor)

Research Advised by Professor Ali Javey

Javey Group:  List of Projects | List of Researchers

BPNX1025: In-Sensor Visible to Mid-Infrared Spectral Machine Vision

Dehui Zhang
Jamie Geng
Shifan Wang
Hyong Min Kim
2025

Multispectral and hyperspectral imaging are important optical inspection technologies. They collect the spatial and spectral information of the incidental light into 3D hypercubes, which can be post-processed into material and structural mapping of the scene. However, acquiring and analyzing the 3D hypercubes set great challenges in data collection, transportation, storage, and computation. The much higher energy, bandwidth, and memory budgets limit the implementation of high-speed, high-resolution hyperspectral imaging to achieve intelligent machine vision. This project introduces an...

BPNX1028: Large Scale Synthesis of Optically Active Tellurium-Based Material

Shu Wang
Naoki Higashitarumizu
2025

Large-scale growth of high-quality semiconductors, the active component of devices, is the foundation of modern electronics. Recently, tellurium (Te) was identified as a promising material for optoelectronics due to its appealing optical properties and potential low-temperature wafer-scale production. In this project, we will develop a new method for controlled and scalable production of optically active tellurium.

Project is currently funded by: Federal

BPNX1024: Reusable Sweat Rate Sensor

Seung-Rok Kim
Yifei Zhan
Noelle Davis
Suhrith Bellamkonda
2025

Sweat rate can provide the precautious signal of hyperhidrosis, hypohidrosis, and autonomic dysfunction. Currently, microfluidic and hygrometer-based sweat rate sensors are two types of available real-time sweat rate sensors. However, microfluidic device has issues of low temporal resolution, limited volume capacity, and surrounding artifact dependencies, while hygrometer-based devices also has overfilling and environmental artifact issues. In this work, we present reusable sweat rate sensor for continuous monitoring of sweat rate with novel sensor design.

Project...

BPNX1022: Multiplexed Gas Sensors

Carla Bassil
2025

Gas sensing has long been an area of academic and industrial interest. However, state of the art sensors still lack selectivity and sensitivity when it comes to differentiating gases of similar compositions. In this work, we explore methods to create multiplexed gas sensors that can differentiate these mixtures with high accuracy and long-term stability.

Project is currently funded by: Federal

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.

...

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...