Category: Publications

Heterogeneous Integration for Silicon Photonic Systems: Challenges and Approaches

Posted on by jdallesa@illinois.edu

The promise of silicon integrated circuits with their electronic or photonic functionality enhanced via heterogeneous integration has motivated significant work in understanding and overcoming the barriers to realizing such an IC. Additional hurdles must be overcome when integrating devices that are highly sensitive to temperature variation such as semiconductor lasers. Challenges in the heterogeneous integration process will be reviewed, and approaches for heterogeneous integration that have the potential to enable silicon ICs with enhanced functionality will be discussed in the context of integrated photonic systems.

IEEE EDTM Article Link

Design and Fabrication Considerations for Transistor-Injected Quantum Cascade Lasers for Compact, Efficient, and Controllable Mid-Wave Infrared Lasing

Posted on by jdallesa@illinois.edu

The transistor-injected quantum cascade laser (TI-QCL) is a novel design for a mid-wave infrared (MWIR) laser that seeks to overcome some of the primary limitations of standard quantum cascade lasers (QCLs). By growing the active cascade region within the base-collector junction of an npn heterojunction bipolar transistor (HBT), independent control of the injection current and active region bias is achievable through the emitter current and base-collector reverse bias respectively. The active region bias is important to properly align the lasing states and to control the lasing wavelength. Physical design limitations of the TI-QCL and their effects on the fabrication process of samples is presented. In order to characterize device performance and validate fabrication improvements, InP-based device samples designed for λ= 7.3 µm emission are fabricated. Preliminary characterization results are shown in the form of diode measurements to validate the HBT electrical operation of the TI-QCL which is necessary to realize the optical benefits of the device.

CS Mantech Article Link

Prof. Dallesasse Interviewed About VCSEL Work

Posted on by Leah Espenhahn

“VCSELs are a type of device that are seeing broad use in a growing number of applications,” said Dallesasse. “They are being looked at for use in self-driving cars that utilize LIDAR, and are already extensively used in the fiber optic networks of large data centers.”

“We’re specifically looking at ways of improving the optical beam that comes out of the VCSEL,” said Dallesasse. “When you have a device like a VCSEL, the optical modes can be thought of as the light patterns on the surface. In order for you to utilize patterns, it’s desirable to be able to control those light patterns.”

UIUC ECE Article Link

Patrick Su, Fu-Chen Hsiao, Tommy O’Brien, and Professor Dallesasse awarded CS MANTECH 2018 Best Student Paper Award

Posted on by psu8@illinois.edu

The Advanced Semiconductor Device and Integration Group was awarded the CS MANTECH 2018 Best Student Paper Award by Patrick Su, Fu-Chen (Alex) Hsiao, Tommy O’Brien and Professor Dallesasse on Controlling Impurity-Induced Disordering via Mask Strain for High-Performance VCSELs.

CS MANTECH 2018 Best Student Paper Award Link Here!

Wafer-Scale Method of Controlling Impurity-Induced Disordering for Optical Mode Engineering in High-Performance VCSELs

Posted on by jdallesa@illinois.edu

The Advanced Semiconductor Device and Integration Group is proud to share a recent publication by Patrick Su, Fu-Chen (Alex) Hsiao, Tommy O’Brien and Professor Dallesasse on demonstrating a novel method of controlling impurity-induce disordering apertures via Mask Strain that can be applied to wafer-scale manufacturing of high-power single-mode VCSELs.

IEEE Transactions in Semiconductor Manufacturing Article Here!

 

Patrick Su and Fu-Chen (Alex) Hsiao are awarded the II-VI Foundation Block-Gift Award

Posted on by psu8@illinois.edu

Patrick Su and Fu-Chen (Alex) Hsiao were awarded the II-VI Foundation Block-Gift award aiming to develop the professional knowledge and experience of Ph.D. candidates. This project is focused on developing single-mode high-power Vertical-Cavity Surface-Emitting Lasers (VCSELs). They are grateful for the support and opportunity provided by the II-VI Foundation.

John Carlson wins Best Poster Award at CS MANTECH 2018

Posted on by psu8@illinois.edu

At the International Compound Semiconductor Manufacturing Technology (CS MANTECH) 2018, John Carlson and Patrick Su were honored with the Best Poster Award on a method of integrating III-V semiconductor material suitable for lasers onto silicon which is used for CMOS electronics. John has demonstrated a novel demonstration of epitaxial bonding and transfer for heterogeneous integration of electron-photonic circuitry.

More details can be found in this link.

Control of Radiative Base Recombination in the Quantum Cascade Light-Emitting Transistor using Quantum State Overlap

Posted on by jdallesa@illinois.edu

The Advanced Semiconductor Device and Integration Group is proud to share a recent publication by Kanuo Chen, Fu-Chen (Alex) Hsiao, Brittany Joy, and Professor Dallesasse on demonstrating the ability to control radiative base recombination in a quantum-cascade light emitting transistor that shows performance benefits of a transistor-injected QCL over conventional QCL devices.

Applied Physics B Article Link

Mode Behavior of VCSELs with Impurity-Induced Disordering by Tommy, Ben, Sam, and Professor Dallesasse

Posted on by jdallesa@illinois.edu

The Advanced Semiconductor Device and Integration Group is proud to share a recent publication by Tommy O’Brien, Ben Kesler, Sam Almulla and Professor Dallesasse exploring the modal behavior of oxide-confined vertical-cavity surface-emitting lasers (VCSELs) with varying emission apertures defined by impurity-induced disordering (IID) via closed ampoule zinc diffusion.

Click Here for Full Article in IEEE Photonic Technology Letters

This work explores the modal behavior of oxide-confined vertical-cavity surface-emitting lasers (VCSELs) with varying emission apertures defined by impurity-induced disordering (IID) via closed ampoule zinc diffusion. A 1-D plane wave propagation method is used to calculate the mirror loss as a function of IID strength and depth. The devices are fabricated with masked areas ranging from approximately 70-110% of the oxide aperture defining an unmodified emission aperture designed to overlap mainly with the fundamental mode. An analysis of the transverse mode lasing characteristics and mode-dependent thermal characteristics demonstrates a decrease in thermal performance associated with the increasing overlap between the IID ring and supported optical modes of the VCSEL cavity. A single-mode output power of 1.6 mW with over 30 dBm SMSR is achieved from a 3.0 μm device with an IID-defined output aperture of approximately 1.3 μm. The optimal IID emission aperture to oxide aperture ratio for maximizing the single-fundamental-mode output power is experimentally measured.

Facilitating Single-Transverse-Mode Lasing in VCSELs via Patterned Dielectric Anti-Phase Filters by Ben, Tommy, Guan-Lin, and Professor Dallesasse

Posted on by jdallesa@illinois.edu

SINGLE-TRANSVERSE-MODE VCSELS VIA PATTERNED DIELECTRIC ANTI-PHASE FILTERS

A novel method to achieve single-fundamental-mode lasing and higher order mode suppresion using a multi-layer, patterned, dielectric anti-phase filter is employed on the top of oxide-confined vertical-cavity surface-emtting lasers (VCSELs).

Click here for Full Article in IEEE Photonics Technology Letters