Process optimization and diffusion length evaluation of a new aqueous base developable negative epoxy electron beam resist

2002 ◽  
Author(s):  
N. Glezos ◽  
P. Argitis ◽  
D. Velessiotis ◽  
I. Raptis ◽  
P. Hudek ◽  
...  
Keyword(s):  
Electron Beam ◽  
Process Optimization ◽  
Diffusion Length ◽  
Aqueous Base ◽  
And Diffusion

Surface recombination effects on minority carrier diffusion length measurements using electron beam-induced current

1990 ◽  
Vol 48 (4) ◽  
pp. 744-745
Author(s):  
D.P. Malta ◽  
M.L. Timmons
Keyword(s):  
Electron Beam ◽  
Beam Energy ◽  
Minority Carrier ◽  
Diffusion Length ◽  
Effective Diffusion ◽  
Surface Recombination ◽  
Surface Recombination Velocity ◽  
Logarithmic Scale ◽  
Minority Carrier Diffusion Length ◽  
Carrier Diffusion

Measurement of the minority carrier diffusion length (L) can be performed by measurement of the rate of decay of excess minority carriers with the distance (x) of an electron beam excitation source from a p-n junction or Schottky barrier junction perpendicular to the surface in an SEM. In an ideal case, the decay is exponential according to the equation, I = Ioexp(−x/L), where I is the current measured at x and Io is the maximum current measured at x=0. L can be obtained from the slope of the straight line when plotted on a semi-logarithmic scale. In reality, carriers recombine not only in the bulk but at the surface as well. The result is a non-exponential decay or a sublinear semi-logarithmic plot. The effective diffusion length (Leff) measured is shorter than the actual value. Some improvement in accuracy can be obtained by increasing the beam-energy, thereby increasing the penetration depth and reducing the percentage of carriers reaching the surface. For materials known to have a high surface recombination velocity s (cm/sec) such as GaAs and its alloys, increasing the beam energy is insufficient. Furthermore, one may find an upper limit on beam energy as the diameter of the signal generation volume approaches the device dimensions.

scholarly journals Can Appropriate Thermal Post-Treatment Make Defect Content in as-Built Electron Beam Additively Manufactured Alloy 718 Irrelevant?

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 536 ◽  
Author(s):  
Sneha Goel ◽  
Kévin Bourreau ◽  
Jonas Olsson ◽  
Uta Klement ◽  
Shrikant Joshi
Keyword(s):  
Electron Beam ◽  
Process Optimization ◽  
Electron Beam Melting ◽  
Phase Distribution ◽  
Hot Isostatic Pressing ◽  
Alloy 718 ◽  
Proof Of Concept ◽  
Defect Content ◽  
Enhancing Production ◽  
Hardness Values

Electron beam melting (EBM) is gaining rapid popularity for production of complex customized parts. For strategic applications involving materials like superalloys (e.g., Alloy 718), post-treatments including hot isostatic pressing (HIPing) to eliminate defects, and solutionizing and aging to achieve the desired phase constitution are often practiced. The present study specifically explores the ability of the combination of the above post-treatments to render the as-built defect content in EBM Alloy 718 irrelevant. Results show that HIPing can reduce defect content from as high as 17% in as-built samples (intentionally generated employing increased processing speeds in this illustrative proof-of-concept study) to <0.3%, with the small amount of remnant defects being mainly associated with oxide inclusions. The subsequent solution and aging treatments are also found to yield virtually identical phase distribution and hardness values in samples with vastly varying as-built defect contents. This can have considerable implications in contributing to minimizing elaborate process optimization efforts as well as slightly enhancing production speeds to promote industrialization of EBM for applications that demand the above post-treatments.

Minority carrier lifetime and diffusion length in type II superlattice barrier devices

2019 ◽  
Vol 96 ◽  
pp. 155-162 ◽  
Author(s):  
P.C. Klipstein ◽  
Y. Benny ◽  
S. Gliksman ◽  
A. Glozman ◽  
E. Hojman ◽  
...  
Keyword(s):  
Carrier Lifetime ◽  
Minority Carrier ◽  
Diffusion Length ◽  
Minority Carrier Lifetime ◽  
Type Ii ◽  
Type Ii Superlattice ◽  
And Diffusion

Equilibrium Spectrum and Diffusion Length in Natural Uranium

1958 ◽  
Vol 3 (6) ◽  
pp. 772-773 ◽  
Author(s):  
D. Meneghetti ◽  
H. H. Hummel ◽  
W. B. Loewenstein
Keyword(s):  
Diffusion Length ◽  
Natural Uranium ◽  
Equilibrium Spectrum ◽  
And Diffusion
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