A Novel n⁺/i-well Dot Ge₁₋ₓSnₓ-on-Si Single-Photon Avalanche Photodiode for High-Fill-Factor Room-Temperature Quantum Applications

Abstract: We propose a novel design of Ge1-xSnx-on-Si single-photon avalanche photodiodes (SPADs) that aim to enhance the fill factor (FF) and minimize noise at room temperature. The device consists of a n+/i-well dot structure designed to eliminate the need for guard rings and multi-dot or array configurations typically used to enhance the active area. This […]

Superconducting Through-Substrate Vias on Sapphire Substrates for Quantum Circuits

Sapphire substrates have recently been recognized for their potential to improve the coherence time of superconducting qubits. However, due to challenges in via fabrication, silicon substrates have been predominantly used for qubits. In this study, we fabricated vias on sapphire substrates using lasers and deposited TiN films by chemical vapor deposition. Cross-sectional views of the […]

Superconducting Through-Substrate Vias on Sapphire Substrates for Quantum Circuits

Sapphire substrates have recently been recognized for their potential to improve the coherence time of superconducting qubits. However, due to challenges in via fabrication, silicon substrates have been predominantly used for qubits. In this study, we fabricated vias on sapphire substrates using lasers and deposited TiN films by chemical vapor deposition. Cross-sectional views of the […]