A5064007751- Photonic and Optical Devices
- Semiconductor Lasers and Optical Devices
- Semiconductor Quantum Structures and Devices
- Semiconductor materials and devices
- Thin-Film Transistor Technologies
- Integrated Circuits and Semiconductor Failure Analysis
- Laser Material Processing Techniques
- Silicon Nanostructures and Photoluminescence
- Nanofabrication and Lithography Techniques
University of Padua
2021-2024
Abstract We evaluate the degradation of 1.3 µm InAs quantum-dot laser diodes epitaxially grown on silicon. For first time, optical mechanisms are investigated by evaluating variations in gain spectra measured during a constant-current stress test. Remarkably, showed that reduction peak modal is dominant compared to increse internal absorption losses. Moreover, increase threshold current (Ith) induced was found be correlated reduction. This experimental evidence modeling variation through...
This article deals for the first time with electrical degradation of novel 845 nm vertical-cavity silicon-integrated lasers (VCSILs) silicon photonics (SiPh). We analyzed reliability these devices by submitting them to high current stress. The experimental results showed that stress induced: 1) a significant increase in series resistance, occurring two separated time-windows and 2) lowering turn-on voltage. To understand origin such phenomena, we simulated <inline-formula...
For the first time we investigate optical degradation of vertical-cavity silicon-integrated lasers VCSILs) designed for operation at 845 nm in photonic integrated circuits (PICs). The study is based on combined electro-optical characterization VCSIL, submitted to constant-current stress tests different current levels. original results obtained within manuscript indicate that related diffusion impurities. Remarkably, depending region through which these impurities are migrating, process...
Abstract The aim of this paper is to identify, analyze and compare the defects present in III-As, as a function dislocation density, presence/absence quantum dots (QDs). Such materials are fundamental importance for development lasers photodiodes silicon photonics. study based on an extensive deep-level transient spectroscopy investigation, carried out GaAs pin diodes grown Si (that differ density), with without embedded QDs. original results described demonstrate that: (a) we were able...
This paper investigates the origin of diffusion process responsible for optical degradation InAs quantum dot (QD) laser diodes epitaxially grown on silicon. By means a series constant-current stress experiments carried out at different temperatures, we were able to quantitatively evaluate temperature acceleration process. In addition, presence thresholds above which rate drastically increases was ascribed onset recombination-enhanced process, is favored high temperatures. Finally, comparison...
We propose a novel methodology capable of separately evaluating the contribution different recombination processes in quantum dot laser diodes (QD LDs) driven below-threshold. The proposed approach is based on analysis subthreshold optical characteristics devices and was used to evaluate variation parameters induced by long-term stress test. results this work indicate that degradation QD LDs mainly increase concentration nonradiative centers within QWs (quantum wells), with consequent...
The fully epitaxial integration of IR laser sources into modern photonic circuits built on Si or SOI wafers is severely limited by the thermal- and lattice-constant mismatch between substrate III-V layers that are required to achieve efficient solid-state lasing in near infrared range. To overcome these limitations, commercially-available SiPh technologies employ selective wafer/device bonding techniques allow separately grow emitter integrate it integrated circuit (PIC) at a later...
For the first time, we analyze optical degradation of 1.3 mm InAs quantum dot laser diodes (QD LDs) epitaxially grown on silicon as a function number dot-in-a-well layers (DWELLs). To this aim, tested reliability two kinds devices differing only in DWELLs active region: QD LDs with three vs. five (3 5 QDLs). induce degradation, submitted to highly accelerated stress tests: current step stress, current, whereas constant evaluated time. Both experiments confirmed that device more QDLs (5×QDLs)...
Silicon photonics is a technology that aims at improving state-of-the-art optical communication systems through high performance lasers, which currently rely mostly on III-As materials grown silicon-on-insulator platforms and, in the future, InAs quantum dots (QDs). In this work, we present an extensive investigation properties of defects IIIAs layers as function presence/absence QDs and dislocation density. By using deep level transient spectroscopy (DLTS), analyzed two kinds devices: GaAs...
Laser diodes are of paramount importance for on-chip telecommunications applications, and a wide range sensing devices that require near-infrared sources. In this work, the under test vertical-cavity silicon-integrated lasers (VCSILs) designed operation at 845 nm in photonic integrated circuits (PICs). We focus on analysis degradation optical performance during aging. To investigate reliability devices, we carried out several stress tests constant current, ranging from 3.5 mA to 4.5...
This paper investigates the role of insertion trapping layers, above and below active region, in improving reliability 1.31 μm InAs quantum-dot laser diodes epitaxially grown on silicon substrate. The study is based an extensive set characterization accelerated aging experiments carried out two groups lasers, featuring same geometry epitaxial structure, but differing presence or absence defect layers. results our work demonstrate that devices with layers exhibit i) higher optical performance...
We discuss the physical processes for degradation of quantum-dot lasers epitaxially grown on silicon. Through combined electro-optical measurements and deep-level transient spectroscopy, we conclude a pathway to obtain significant improvement in device lifetime.
Optical and electrical degradation of novel micro-transfer-printed VCSILs is investigated. Modeling experimental data suggests that the main mechanism represented by relocation impurities, originating from p-side, toward active region.
We review the latest results on physical cause for degradation of heterogeneous and quantum-dot based infrared laser diodes. Such devices are a fundamental building block photonic integrated circuits silicon photonics applications. One most critical fabrication steps is integration III-V semiconductors active device silicon-on insulator wafer providing waveguiding additional electronic components. option to achieve by bonding two wafers together. Devices fabricated in this way do not suffer...
In this work we present the electrical modeling of novel 845 nm vertical-cavity silicon-integrated lasers (VCSILs) for silicon photonics (SiPh). We tested reliability devices by submitting them to high current stress, corresponding ≈ 20xI <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</inf> , observe degradation as a function time. During stress experiment, monitored characteristics at regular intervals and observed two separate phenomena:...
This paper investigates the temperature dependence of optical degradation InAs quantum-dot (QD) lasers grown on silicon, and its relation with impurity diffusion processes. goal was achieved by submitting a group identical 1.3 μm QD LDs Si to series constant-current stress experiments at baseplate temperatures ranging from 15 °C 75 °C. The analysis threshold current (I<sub>th</sub>) kinetics revealed that process i) is not activated for junction (T<sub>j</sub>) lower than 60...