Search arXivSearch

arXiv · 1707.00582

Reduced Low Dose Rate Sensitivity and its Mechanism in Bipolar Junction Transistors

Abstract

It is surprising that only an enhanced low-dose-rate sensitivity (ELDRS), but not its contrariety, a reduced low-dose-rate sensitivity (RLDRS), is experimentally observed in bipolar junction transistors. In this work, we attribute this strong asymmetry to an overwhelming superiority of hydrogen cracking reactions relative to Shockley-Read-Hall recombinations. We demonstrate that this situation can be completely reversed and an RLDRS effect can occur by decreasing the concentration ratio between hydrogen and recombination centers. We show that the decrease of recombination rate of holes (generation rate of protons) with increasing dose rate is responsible for the positive (negative) dose-rate dependence of RLDRS (ELDRS). We also find an RLDRS-ELDRS transition for decreasing dose rate, in which the transition point can be controlled by the concentration ratio. The proposed RLDRS effect and its tunability pave a way for a credible acceleration test of the total ionizing dose damage in different low dose rate environments.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Xiao-Long Feng, Zi-Bo Wang, Yang Liu, Yu Song. 2017-07-03. Reduced Low Dose Rate Sensitivity and its Mechanism in Bipolar Junction Transistors. https://arxiv.org/abs/1707.00582

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

First Observation of a Polar Coronal Hole-like Fast Solar Wind Stream in the Sub-Alfvénic Solar Corona: an Analysis of Turbulence Properties

Parker Solar Probe, near its 23rd perihelion in March 2025, sampled an extended interval of sub-Alfvénic solar wind likely originating from a large equatorial coronal hole. At heliocentric distances of approximately 10 solar radii, with speed mostly above 400 km/s, this interval is a first example of ``polar coronal hole-like (PCH-l) fast" solar wind observed in the sub-Alfvénic solar corona. We characterize the turbulence properties of this unique interval using Parker Solar Probe measurements. Despite being sampled well inside the nominal Alfvén surface, the turbulence appears to be already well developed while remaining strongly transverse and highly imbalanced, exhibiting a large cross helicity. These observations provide new constraints on the development and evolution of solar wind turbulence within the lower corona.

physics.space-ph

Coordinate Systems and Transforms in Space Physics: Terms, Definitions, Implementations, and Recommendations for Reproducibility

In space physics, acronyms for coordinate systems (e.g., \texttt{GEI}, \texttt{GSM}) are commonly used; however, differences in their definitions and implementations can prevent reproducibility. In this work, we compare definitions in online resources, software packages, and frequently cited journal articles and show that implementation differences can lead to transformations between same-named coordinate systems and position values from different data providers to differ significantly. Based on these comparisons and results, and to enable reproducibility, we recommend that (a) a standard for acronyms and definitions for coordinate systems is developed, similar to equivalents in astronomy or earth sciences; (b) a standards body develops a citable database of reference data needed for these transforms. For software that computes coordinate transforms, we also recommend that their developers provide explicit comparisons of their implementations with the results of (b) and documentation on implementation choices. Additionally, we provide recommendations for scientists and metadata developers to ensure that sufficient information is provided to enable reproducibility. Finally, we document that spacecraft positions from data providers can differ both because of differences in how they implemented transforms and because of differences in the original source of the position data, and provide recommendations to improve the documentation of spacecraft positional datasets.

physics.space-ph

Aurora Hunter: A Two-Stage Framework for Probabilistic Visibility Forecasting

Aurora visibility at a given location requires two physically distinct conditions to hold at once: aurora occurring overhead, governed by solar wind-magnetosphere coupling, and observing conditions that permit detection, governed by cloud cover and moonlight. Approaches that conflate the two weaken the space-weather signal and limit cross-site generalizability. We develop Aurora Hunter, a two-stage cascade that separates occurrence prediction from observing-condition assessment. Stage 1 uses 43 physics-driven features to predict P(aurora identifiable in all-sky images) via gradient-boosted trees trained on joint Tromso+Kiruna data (about 16,600 hours, 2015-2023). Stage 2 models P(unobscured image class | identifiable) with logistic regression on 15 observing-condition features, trained on hours with identifiable aurora. The cascade P(visible) = P(identifiable) x P(unobscured | identifiable) achieves retrospective ROC-AUC of 0.958 (Tromso test, 2019-2020) and 0.933 (independent Kiruna, 2024), improving on the occurrence stage used alone by +0.095 and +0.097. Transfer to Skibotn, the one station withheld entirely (2022-2025), is limited. SHAP analysis identifies magnetic local time, the Kp x nightside interaction and the three-hour mean Kp as the dominant features (44% of attribution), consistent with auroral oval physics. Hemisphere-wide occurrence maps combine the Stage 1 amplitude, on a clear-sky basis, with the Feldstein oval parameterization. By providing location-specific visibility probabilities with measured reliability rather than coarse geomagnetic indices, the framework links space weather research to practical observation planning. An operational proof of concept is available at https://aurora-hunter.onrender.com

physics.space-ph