Related Experiment Video
Updated: Jul 12, 2025
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
9.7K
Very low excess noise Al0.75Ga0.25As0.56Sb0.44 avalanche photodiode
Optics Express
|October 20, 2023
Summary
This study reveals lower excess noise in AlGaAsSb avalanche photodiodes (APDs) at high multiplication, achieving record low noise for III-V APDs. These findings advance APD design and high-field device applications.
Area of Science:
- Semiconductor Physics
- Optoelectronics
- Materials Science
Background:
- AlxGai-xAsySb1-y on InP is researched for low-noise, high-sensitivity avalanche photodiodes (APDs).
- Previous work focused on high Al concentrations (x >= 0.85).
Purpose of the Study:
- To investigate AlGaAsSb with lower Al concentrations for improved APD performance.
- To determine impact ionization coefficients and excess noise in Al0.75Ga0.25As0.56Sb0.44.
Main Methods:
- Fabrication and characterization of complementary p-i-n and n-i-p diode structures.
- Measurement of avalanche multiplication and excess noise over a wide electric field range (up to 650 kV/cm).
Main Results:
- Achieved excess noise factor (F=2.4) at high multiplication (M=90) in Al0.75Ga0.25As0.56Sb0.44.
- Determined electron and hole impact ionization coefficients.
- Observed excess noise significantly lower than predicted by conventional McIntyre theory.
Conclusions:
- AlGaAsSb with lower Al concentrations offers superior low-noise performance in APDs.
- Results challenge existing noise theories and have implications for high-field devices beyond APDs.
Related Concept Videos
01:27Schottky Barrier Diode
370
Schottky barrier diodes are specialized semiconductor devices characterized by their unique construction. This construction involves combining a metal layer with a moderately doped n-type semiconductor material. This combination leads to the formation of a Schottky barrier, a pivotal element that defines the diode's operational characteristics. The core functionality of Schottky barrier diodes is their capacity to allow current to flow in only one direction due to their distinctive...
370
01:20Diode: Forward bias
1.1K
In semiconductor devices, diodes play a crucial role in directing current flow, and its operation is primarily categorized into forward bias and reverse bias. A diode is said to be forward-biased when its p-type region is connected to the positive terminal of a battery and its n-type region is linked to the negative terminal. This configuration reduces the potential barrier within the diode, allowing current to flow easily from the p to the n-type region.
The behavior of a diode in forward bias...
The behavior of a diode in forward bias...
1.1K
01:14Diode: Reverse bias
762
A diode is reverse-biased when the positive terminal of an external voltage source is connected to the n-type material and the negative terminal to the p-type material. This configuration opposes the natural direction of current flow through the diode, effectively increasing the width of the depletion region and the barrier potential. The reverse bias condition produces a minimal leakage current, primarily due to minority charge carriers. This leakage becomes significant when the reverse...
762