View in EDS

Emergence of Negative Differential Resistance Through Hole Resonant Tunneling in GeSn/GeSiSn Double Barrier Structure

Saved in:
Bibliographic Details
Title: Emergence of Negative Differential Resistance Through Hole Resonant Tunneling in GeSn/GeSiSn Double Barrier Structure
Authors: Shigehisa Shibayama, Shuto Ishimoto, Yoshiki Kato, Mitsuo Sakashita, Masashi Kurosawa, Osamu Nakatsuka
Source: IEEE Journal of the Electron Devices Society, Vol 13, Pp 79-85 (2025)
Publisher Information: Institute of Electrical and Electronics Engineers (IEEE), 2025.
Publication Year: 2025
Subject Terms: double barrier structure, germanium-silicon-tin (GeSiSn), epitaxial growth, Germanium (Ge), heterostructure, Electrical engineering. Electronics. Nuclear engineering, germanium-tin (GeSn), TK1-9971
Description: We examined the fabrication and the operation of GeSn/GeSiSn resonant tunneling diode (RTD) and demonstrated the observation of negative differential resistance (NDR) at a low temperature through the hole resonant tunneling. First, we revealed the possible designed contents of GeSiSn to Si and Sn of 40–60% and ∼10%, respectively to achieve the valence band offset over 0.3 eV with sustaining the biaxial strain value less than 1.0%, which is an important factor for the pseudomorphic growth of GeSn/GeSiSn heterostructure on Ge. Then, we successfully fabricated GeSn/GeSiSn RTD with a double barrier structure composed of ultra-thin GeSiSn barriers and GeSn well, which has the steep heterointerface. The current-density–voltage (J–V) characteristics at 10 K of the fabricated GeSn/GeSiSn RTD showed NDRs at applied voltages of approximately −1.5 and −1.8 V with peak to valley current ratio of 1.06 and 1.14, respectively, and peak current density of ∼3 and ∼5 kA/cm2, respectively. We also demonstrated that the observed NDR is reproducible. The quantum level and J–V simulations suggests that these two NDRs would originate from the hole resonant tunneling current through the first and second quantum levels formed in the GeSn well layer. Furthermore, we also discussed issues newly found in this study and future remarks of GeSn/GeSiSn heterostructures as RTD applications for the terahertz oscillator and the nonvolatile RAM.
Document Type: Article
ISSN: 2168-6734
DOI: 10.1109/jeds.2025.3529079
Access URL: https://doaj.org/article/f62ae4f0580447199938bbdbb22cde03
Rights: CC BY NC ND
Accession Number: edsair.doi.dedup.....7477d476a0f568527fa2937187c8e26d
Database: OpenAIRE
Description
Abstract:We examined the fabrication and the operation of GeSn/GeSiSn resonant tunneling diode (RTD) and demonstrated the observation of negative differential resistance (NDR) at a low temperature through the hole resonant tunneling. First, we revealed the possible designed contents of GeSiSn to Si and Sn of 40–60% and ∼10%, respectively to achieve the valence band offset over 0.3 eV with sustaining the biaxial strain value less than 1.0%, which is an important factor for the pseudomorphic growth of GeSn/GeSiSn heterostructure on Ge. Then, we successfully fabricated GeSn/GeSiSn RTD with a double barrier structure composed of ultra-thin GeSiSn barriers and GeSn well, which has the steep heterointerface. The current-density–voltage (J–V) characteristics at 10 K of the fabricated GeSn/GeSiSn RTD showed NDRs at applied voltages of approximately −1.5 and −1.8 V with peak to valley current ratio of 1.06 and 1.14, respectively, and peak current density of ∼3 and ∼5 kA/cm2, respectively. We also demonstrated that the observed NDR is reproducible. The quantum level and J–V simulations suggests that these two NDRs would originate from the hole resonant tunneling current through the first and second quantum levels formed in the GeSn well layer. Furthermore, we also discussed issues newly found in this study and future remarks of GeSn/GeSiSn heterostructures as RTD applications for the terahertz oscillator and the nonvolatile RAM.
ISSN:21686734
DOI:10.1109/jeds.2025.3529079