scholarly journals Изготовление сверхпроводниковых туннельных структур с использованием электронно-лучевой литографии

2021 ◽  
Vol 63 (9) ◽  
pp. 1228
Author(s):  
М.Ю. Фоминский ◽  
Л.В. Филиппенко ◽  
А.М. Чекушкин ◽  
В.П. Кошелец
Keyword(s):  
Tunnel Junctions ◽  
High Current Density ◽  
Exposure Dose ◽  
Quality Parameter ◽  
Lower Sensitivity ◽  
High Current ◽  
Plasma Chemical ◽  
Plasma Chemical Etching ◽  
Etching Parameters

The technology for manufacturing submicron Nb - AlN - NbN tunnel junctions using electron beam lithography has been developed and optimized. Investigations have been carried out to select the exposure dose, development time, and plasma-chemical etching parameters to obtain the high quality of junctions (the ratio of the resistances below and above the gap Rj/Rn). The use of a negative resist ma-N 2400 with lower sensitivity and better contrast in comparison with a negative resist UVN 2300-0.5 has improved the reproducibility of the structure fabrication process. The submicron (area from 2.0 to 0.2 µm2) tunnel junctions Nb - AlN - NbN with high current density and quality parameter Rj / Rn> 15 were fabricated. The spread of parameters of submicron tunnel structures across the substrate and the reproducibility of the cycle-to-cycle process of fabrication of tunnel structures has been experimentally measured.

scholarly journals Fabrication of Superconducting Nb–AlN–NbN Tunnel Junctions Using Electron-Beam Lithography

Electronics ◽  
2021 ◽  
Vol 10 (23) ◽  
pp. 2944
Author(s):  
Mikhail Yu. Fominsky ◽  
Lyudmila V. Filippenko ◽  
Artem M. Chekushkin ◽  
Pavel N. Dmitriev ◽  
Valery P. Koshelets
Keyword(s):  
Electron Beam ◽  
Electron Beam Lithography ◽  
Tunnel Junctions ◽  
Intrinsic Noise ◽  
Exposure Dose ◽  
Quality Parameters ◽  
Lower Sensitivity ◽  
Input Devices ◽  
Plasma Chemical Etching ◽  
Etching Parameters

Mixers based on superconductor–insulator–superconductor (SIS) tunnel junctions are the best input devices at frequencies from 0.1 to 1.2 THz. This is explained by both the extremely high nonlinearity of such elements and their extremely low intrinsic noise. Submicron tunnel junctions are necessary to realize the ultimate parameters of SIS receivers, which are used as standard devices on both ground and space radio telescopes around the world. The technology for manufacturing submicron Nb–AlN–NbN tunnel junctions using electron-beam lithography was developed and optimized. This article presents the results on the selection of the exposure dose, development time, and plasma chemical etching parameters to obtain high-quality junctions (the ratio of the resistances below and above the gap Rj/Rn). The use of a negative-resist ma-N 2400 with lower sensitivity and better contrast in comparison with a negative-resist UVN 2300-0.5 improved the reproducibility of the structure fabrication process. Submicron (area from 2.0 to 0.2 µm2) Nb–AlN–NbN tunnel junctions with high current densities and quality parameters Rj/Rn > 15 were fabricated. The spread of parameters of submicron tunnel structures across the substrate and the reproducibility of the cycle-to-cycle process of tunnel structure fabrication were measured.

scholarly journals Very high-current-density Nb/AlN/Nb tunnel junctions for low-noise submillimeter mixers

2000 ◽  
Vol 76 (15) ◽  
pp. 2119-2121 ◽  
Author(s):  
Jonathan Kawamura ◽  
David Miller ◽  
Jian Chen ◽  
Jonas Zmuidzinas ◽  
Bruce Bumble ◽  
...  
Keyword(s):  
Current Density ◽  
Tunnel Junctions ◽  
High Current Density ◽  
Low Noise ◽  
High Current ◽  
Very High

NbN/AlN/NbN tunnel junctions with high current density up to 54 kA/cm2

1997 ◽  
Vol 70 (1) ◽  
pp. 114-116 ◽  
Author(s):  
Zhen Wang ◽  
Akira Kawakami ◽  
Yoshinori Uzawa
Keyword(s):  
Current Density ◽  
Tunnel Junctions ◽  
High Current Density ◽  
High Current

1/f noise in high current density NbN/AlN/NbN tunnel junctions

2001 ◽  
Vol 11 (1) ◽  
pp. 84-87 ◽  
Author(s):  
Zhen Wang ◽  
A. Kawakami ◽  
A. Saito ◽  
K. Hamasaki
Keyword(s):  
Current Density ◽  
Tunnel Junctions ◽  
High Current Density ◽  
High Current

КОМПЛЕКС БАЗОВЫХ ТЕХНОЛОГИЧЕСКИХ ПРОЦЕССОВ ДЛЯ ПОЛУЧЕНИЯ МОЩНЫХ ПОЛЕВЫХ ТРАНЗИСТОРОВ И МИС СВЧ-ДИАПАЗОНА НА ОСНОВЕ GAN И GAAS С ИСПОЛЬЗОВАНИЕМ ОТЕЧЕСТВЕННОГО ОБОРУДОВАНИЯ

2020 ◽  
Vol 96 (3s) ◽  
pp. 343-346
Author(s):  
А.Н. Алексеев ◽  
С.И. Петров
Keyword(s):  
Ohmic Contacts ◽  
Field Effect Transistors ◽  
Production Cycle ◽  
Electronic Industry ◽  
Plasma Chemical ◽  
High Power Field ◽  
Mbe Growth ◽  
Technological Processes ◽  
Plasma Chemical Etching ◽  
Problems And Solutions

Представлены результаты разработки базовых технологических процессов, используемых при получении мощных полевых транзисторов и МИС СВЧ-диапазона на основе GaN и GaAs, таких как: выращивание гетероструктур методом МЛЭ, металлизация и отжиг омических контактов, травление мезаизоляции, затворная металлизация, пассивация диэлектриком и др. Обсуждаются основные проблемы и пути их решения, в том числе особенности технологических процессов глубокого плазмохимического травления для формирования сквозных металлизированных отверстий в SiC и GaAs. Отдельное внимание уделено вопросам обеспечения однородности и воспроизводимости и их влиянию на выход годных структур. Продемонстрированы результаты использования ряда технологических процессов в производственном цикле АО «Светлана-Рост» и других предприятий радиоэлектронной промышленности. The paper presents the results of the development of basic technological processes used in the production of microwave high-power field-effect transistors based on GaN and GaAs such as: MBE growth, metallization and annealing of ohmic contacts, etching of mesa insulation, gate metallization, passivation by dielectric etc. The main problems and solutions including features of technological processes of deep plasma-chemical etching in SiC and GaAs have been discussed. Special attention is paid to the issues of uniformity and reproducibility and their impact on the yield of structures. The results of the use of technological processes in the production cycle of Svetlana-Rost JSC and other enterprises of the radio-electronic industry have been demonstrated.

Galvanostatic dissolution of mercury from the surface of glassy carbon into thiocyanate solution

1980 ◽  
Vol 45 (1) ◽  
pp. 169-178 ◽  
Author(s):  
František Opekar ◽  
Karel Holub
Keyword(s):  
Glassy Carbon ◽  
Electrode Surface ◽  
High Current Density ◽  
High Current ◽  
Nernst Equation ◽  
Potential Oscillations ◽  
Thiocyanate Solution ◽  
Theoretical Assumptions ◽  
Solution Proceeds ◽  
Dissolution Current

The galvanostatic dissolution of mercury from the surface of glassy carbon into a thiocyanate solution proceeds in accord with theoretical assumptions, as manifested by the constant product of the dissolution current and transition time. Under certain relations between the amount of oxidised mercury and concentration of thiocyanate at the electrode surface, however, a small part of the mercury dissolves at more positive potentials than correspond to the Nernst equation. This dissolution can be accompanied by potential oscillations. The anomalous behaviour is elucidated by the concept about coverage of a certain part of mercury with a film of sparingly soluble compounds of SCN- ions with mercury. This film is formed at the end of the galvanostatic dissolution on certain places of the electrode surface covered with mercury droplets, where SCN- ions are much exhausted as a result of a high current density.

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