Space Charge Limited Current and Induced Particle Reflection With a Time-Varying Current Injection

• Published in: IEEE transactions on electron devices Vol. 69; no. 8; pp. 4460 - 4468
• Main Authors: Zhu, Ying Bin, Liao, Mei Yan, Yao, Ruo He
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.08.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Cathodes; Constraining; Current density; Current injection; Electric potential; Electrodes; Electrons; Limiting; Mathematical models; Numerical models; Particle reflection; Space charge; space charge limited; space charge oscillations
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2022.3186868

Properties of space charge limited current and induced particle reflection with a time-varying current injection are investigated by an efficient grid-free numerical approach. Considering a planar diode with a single-frequency current emitted parallel to the upstream electrode surface, we study the current transmission characteristics between two dc biased electrodes and the influence of current frequency and magnitude on the limiting current first leading to electrons reflection. It is found that on account of the time-varying current injection, the limiting current strongly depends on the current frequency and magnitude, as well as the emission velocity of electrons. For the low-frequency limit, the dc component of the limiting current is approximately equal to half of that obtained from the time-independent model. The limiting current increases monotonically with increasing the frequency, and the dc component has a maximum equal to the limiting current obtained from the time-independent model.