Thin structure of near-field emission of semiconductor laser

2004 ◽  
Author(s):  
K. P. Gaikovich ◽  
V. F. Dryakhlushin
Keyword(s):  
Semiconductor Laser ◽  
Field Emission ◽  
Near Field ◽  
Thin Structure

Fundamental Aspects of Near-Field Emission Scanning Electron Microscopy

2012 ◽  
pp. 227-258 ◽  
Author(s):  
D.A. Zanin ◽  
H. Cabrera ◽  
L.G. De Pietro ◽  
M. Pikulski ◽  
M. Goldmann ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Field Emission ◽  
Near Field ◽  
Scanning Electron

scholarly journals Exact eigenstates of a nanometric paraboloidal emitter and field emission quantities

2018 ◽  
Vol 474 (2214) ◽  
pp. 20170692 ◽  
Author(s):  
A. Chatziafratis ◽  
G. Fikioris ◽  
J. P. Xanthakis
Keyword(s):  
Schrödinger Equation ◽  
Field Emission ◽  
Schrodinger Equation ◽  
Near Field ◽  
Plane Waves ◽  
Spot Size ◽  
Emission Angle ◽  
Electron Velocity ◽  
Cartesian Geometry ◽  
Tip Radius

The progress in field emission theory from its initial Fowler–Nordheim form is centred on the transmission coefficient. For the supply (of electrons) function one still uses the constant value due to a supply of plane-waves states. However, for emitting tips of apex radius of 1–5 nm this is highly questionable. To address this issue, we have solved the Schrödinger equation in a sharp paraboloidally shaped quantum box. The Schrödinger equation is separable in the rotationally parabolic coordinate system and we hence obtain the exact eigenstates of the system. Significant differences from the usual Cartesian geometry are obtained. (1) Both the normally incident and parallel electron fluxes are functions of the angle to the emitter axis and affect the emission angle. (2) The WKB approximation fails for this system. (3) The eigenfunctions of the nanoemitter form a continuum only in one dimension while complete discretization occurs in the other two directions. (4) The parallel electron velocity vanishes at the apex which may explain the recent spot-size measurements in near-field scanning electron microscopy. (5) Competing effects are found as the tip radius decreases to 1 nm: The electric field increases but the total supply function decreases so that possibly an optimum radius exists.

Die Bonding of High Power 808 nm Laser Diodes With Nanosilver Paste

2012 ◽  
Vol 134 (4) ◽  
Author(s):  
Yi Yan ◽  
Xu Chen ◽  
Xingsheng Liu ◽  
Yunhui Mei ◽  
Guo-Quan Lu
Keyword(s):  
Semiconductor Laser ◽  
High Power ◽  
Near Field ◽  
Laser Diodes ◽  
Acoustic Microscopy ◽  
High Power Laser ◽  
Power Laser ◽  
Power Semiconductor ◽  
Die Bonding ◽  
Nanosilver Paste

Conduction-cooled high power laser diodes have a variety of significant commercial, industrial, and military applications. For these devices to perform effectively, an appropriate die-attached material meeting specific requirements must be selected. In this study, nanosilver paste, a novel die-attached material, was used in packaging the 60 W 808 nm high power laser diodes. The properties of the laser diodes operating in the continuous wave (CW) mode, including the characteristics of power–current–voltage (LIV), spectrum, near field, far field, near field linearity, spatial spectrum, and thermal impedance, were determined. In addition, destructive tests, including the die shear test, scanning acoustic microscopy, and the thermal rollover test, were conducted to evaluate the reliability of the die bonding of the 60 W 808 nm high power semiconductor laser with nanosilver paste. Thermal analyses of the laser diodes operating at CW mode with different die-attached materials, indium solder, gold–tin solder and nanosilver paste, were conducted by finite element analysis (FEA). According to the result of the FEA, the nanosilver paste resulted in the lowest temperature in the laser diodes. The test results showed that the nanosilver paste was a very promising die-attached material in packaging high power semiconductor laser.

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