Choice of Si doping type for optimizing the performances of a SiOx-based tunneling electron source fabricated on SiOx/Si substrate

GaN Schottky barrier ultraviolet photodetectors with unintentionally doped GaN and lightly Si-doped n−-GaN absorption layers were successfully fabricated, respectively. The high-quality GaN films on the Si substrate both have a fairly low dislocation density and point defect concentration. More importantly, the effect of Si doping on the performance of the GaN-on-Si Schottky barrier ultraviolet photodetector was studied. It was found that light Si doping in the absorption layer can significantly increase the responsivity under reverse bias, which might be attributed to the persistent photoconductivity that originates from the lowering of the Schottky barrier height. In addition, the devices with unintentionally doped GaN demonstrated a relatively high-speed photo response. We briefly studied the mechanism of changes in Schottky barrier, dark current and the characteristic of response time.

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A Miniature Ionization Vacuum Sensor With a SiOₓ-Based Tunneling Electron Source

IEEE Transactions on Electron Devices ◽

10.1109/ted.2021.3102089 ◽

2021 ◽

Vol 68 (10) ◽

pp. 5127-5132

Author(s):

Wei Yang ◽

Wenchao Liu ◽

Xun Wang ◽

Zhiwei Li ◽

Fangyuan Zhan ◽

...

Keyword(s):

Electron Source ◽

Tunneling Electron ◽

Vacuum Sensor

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Структурное совершенство и состав легированных галлием термомиграционных слоев кремния

Письма в журнал технической физики ◽

10.21883/pjtf.2020.06.49161.18153 ◽

2020 ◽

Vol 46 (6) ◽

pp. 27

Author(s):

А.А. Ломов ◽

Б.М. Середин ◽

С.Ю. Мартюшов ◽

А.Н. Заиченко ◽

С.Г. Симакин ◽

...

Keyword(s):

Mass Spectrometry ◽

Power Electronics ◽

Secondary Ion Mass Spectrometry ◽

Formation Temperature ◽

Si Substrate ◽

Single Crystalline ◽

X Ray ◽

Si Doping ◽

Ion Mass Spectrometry ◽

Secondary Ion

We suggest a technique of fabrication of thick heavily Ga doped by thermomigration layers of Si for modern power electronics devices. Structure perfection and layers composition as a function of formation temperature were studied by techniques of X-ray Lang topography, X-ray rocking curves and secondary ion mass spectrometry. The fabricated layers are single crystalline, no mismatch dislocations were found on the interface with the Si substrate. The Ga concentration in the layers can be varied in the range (1.6-4.8)1019 cm-3, being higher than for Si doping with aluminum.

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Effect of Si Doping on Epitaxial Lateral Overgrowth of GaAs on GaAs-Coated Si Substrate

Japanese Journal of Applied Physics ◽

10.1143/jjap.31.l359 ◽

1992 ◽

Vol 31 (Part 2, No. 3B) ◽

pp. L359-L361 ◽

Cited By ~ 38

Author(s):

Seiichi Sakawa ◽

Tatau Nishinaga

Keyword(s):

Epitaxial Lateral Overgrowth ◽

Si Substrate ◽

Si Doping ◽

Lateral Overgrowth

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A Shelved Structure for the Support of An Electron Optical Column

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068825 ◽

1970 ◽

Vol 28 ◽

pp. 366-367

Author(s):

P.H. McLaughlin

Keyword(s):

Electron Source ◽

Floating Platform ◽

Supporting Structure

A shelved structure for the support of an electron optical column affords advantages both to the designer and the user. A lens may be removed for cleaning for example, without demounting the remaining lenses. A custom device for another example, may be placed on a shelf, substituting for the standard lens perhaps so that some specialized research may be undertaken. Especially advantageous is a shelved arrangement if the column assembly is designed to hang from a supporting structure such as a gas borne floating platform, as is the case with the system described below.As shown on the schematic, a floating platform (I) supports the electron source apparatus (2) and a U-shaped column support shelf (3). The column support shelf acts as a key for locating and supporting three struts (4) which with nuts (5) support the condenser shelf (6), the objective shelf (7), the upper projector shelf (8), and the lower projector shelf (9).

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Transmission Electron Microscopy studies of the vacancy ordering in YSI2-X thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087124 ◽

1991 ◽

Vol 49 ◽

pp. 562-563

Author(s):

F.-R. Chen ◽

T. L. Lee ◽

L. J. Chen

Keyword(s):

Crystal Structure ◽

Electron Microscopy ◽

Thin Films ◽

Diffraction Pattern ◽

Annealing Temperature ◽

Lattice Mismatch ◽

Si Substrate ◽

Metal Thin Films ◽

Transmission Electron ◽

Vacancy Ordering

YSi2-x thin films were grown by depositing the yttrium metal thin films on (111)Si substrate followed by a rapid thermal annealing (RTA) at 450 to 1100°C. The x value of the YSi2-x films ranges from 0 to 0.3. The (0001) plane of the YSi2-x films have an ideal zero lattice mismatch relative to (111)Si surface lattice. The YSi2 has the hexagonal AlB2 crystal structure. The orientation relationship with Si was determined from the diffraction pattern shown in figure 1(a) to be and . The diffraction pattern in figure 1(a) was taken from a specimen annealed at 500°C for 15 second. As the annealing temperature was increased to 600°C, superlattice diffraction spots appear at position as seen in figure 1(b) which may be due to vacancy ordering in the YSi2-x films. The ordered vacancies in YSi2-x form a mesh in Si plane suggested by a LEED experiment.

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Optical Properties of HVEM Accelerators

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100114529 ◽

1975 ◽

Vol 33 ◽

pp. 180-181

Author(s):

A. Strojnik ◽

J.W. Scholl ◽

V. Bevc

Keyword(s):

Optical Properties ◽

Electron Accelerator ◽

Systematic Investigation ◽

Electron Source ◽

High Brightness ◽

The Past ◽

Wide Range ◽

Optical Behavior

The electron accelerator, as inserted between the electron source (injector) and the imaging column of the HVEM, is usually a strong lens and should be optimized in order to ensure high brightness over a wide range of accelerating voltages and illuminating conditions. This is especially true in the case of the STEM where the brightness directly determines the highest resolution attainable. In the past, the optical behavior of accelerators was usually determined for a particular configuration. During the development of the accelerator for the Arizona 1 MEV STEM, systematic investigation was made of the major optical properties for a variety of electrode configurations, number of stages N, accelerating voltages, 1 and 10 MEV, and a range of injection voltages ϕ0 = 1, 3, 10, 30, 100, 300 kV).

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A comparative study on the cold type and thermal type field emission guns used in the same electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107435 ◽

1978 ◽

Vol 36 (1) ◽

pp. 58-59

Author(s):

M. Iwatsuki ◽

Y. Kokubo ◽

Y. Harada

Keyword(s):

Electron Microscope ◽

Field Emission ◽

Signal To Noise Ratio ◽

Electron Source ◽

Resolving Power ◽

Optical Source ◽

Experimental Conditions ◽

High Brightness ◽

Illumination System ◽

Transmission Electron

On accout of its high brightness, small optical source size, and minimal energy spread, the field emission gun (FEG) has the advantage that it provides the conventional transmission electron microscope (TEM) with a highly coherent illumination system and directly improves the resolving power and signal-to-noise ratio of the scanning electron microscope (SEM). The FEG is generally classified into two types; the cold field emission (C-FEG) and thermal field emission gun (T-FEG). The former, in which a field emitter is used at the room temperature, was successfully developed as an electron source for the SEM. The latter, in which the emitter is heated to the temperature range of 1000-1800°K, was also proved to be very suited as an electron source for the TEM, as well as for the SEM. Some characteristics of the two types of the FEG have been studied and reported by many authors. However, the results of the respective types have been obtained separately under different experimental conditions.

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Electron microscopy studies of PZT ferroelectric film capacitor structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131450 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1364-1365

Author(s):

V. Kaushik ◽

P. Maniar ◽

J. Olowolafe ◽

R. Jones ◽

A. Campbell ◽

...

Keyword(s):

Electric Fields ◽

Sol Gel ◽

Ferroelectric Material ◽

Dielectric Constants ◽

Dielectric Films ◽

Lead Zirconium Titanate ◽

Si Substrate ◽

Film Capacitor ◽

Pzt Films ◽

High Dielectric

Lead zirconium titanate films (Pb (Zr,Ti) O3 or PZT) are being considered for potential application as dielectric films in memory technology due to their high dielectric constants. PZT is a ferroelectric material which shows spontaneous polarizability, reversible under applied electric fields. We report herein some results of TEM studies on thin film capacitor structures containing PZT films with platinum-titanium electrodes.The wafers had a stacked structure consisting of PZT/Pt/Ti/SiO2/Si substrate as shown in Figure 1. Platinum acts as electrode material and titanium is used to overcome the problem of platinum adhesion to the oxide layer. The PZT (0/20/80) films were deposited using a sol-gel method and the structure was annealed at 650°C and 800°C for 30 min in an oxygen ambient. XTEM imaging was done at 200KV with the electron beam parallel to <110> zone axis of silicon.Figure 2 shows the PZT and Pt layers only, since the structure had a tendency to peel off at the Ti-Pt interface during TEM sample preparation.

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