Preparation of GaN-based cross-sectional TEM specimens by laser lift-off

Micron ◽  
2005 ◽  
Vol 36 (3) ◽  
pp. 281-284 ◽  
Author(s):  
Li Zilan ◽  
Hu Xiaodong ◽  
Chen Ke ◽  
Nie Ruijuan ◽  
Luo Xuhui ◽  
...  
Keyword(s):  
Cross Sectional ◽  
Lift Off

A Polishless Method For Preparation Of Cross-Sectional Tem Samples

1987 ◽  
Vol 115 ◽  
Author(s):  
J. T. Wetzel ◽  
D. A. Danner
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ion Beam ◽  
Ease Of Use ◽  
Traditional Methods ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Lift Off ◽  
Materials Used ◽  
Transparent Area

ABSTRACTCross-sectional samples for Transmission Electron Microscopy (TEM) have been made without the use of mechanical polishing and ion beam milling. Instead of traditional methods, we have used a combination of electron beam (e-beam) lithography for metal lift-off and reactive ion etching (RIE) to produce TEM samples of selected areas. The sample integrity for handling, dropping and ease of use is excellent, and the large amount of transparent area available for study is nearly 2 orders of magnitude larger than that given by traditional methods. The thickness of the samples is somewhat extreme, on the order of 0.50–1.0μm, but efforts are being made to reduce this dimension in order to make the method applicable to the whole range of materials used in silicon technology.

Comparative analysis on the film cooling mechanisms of elliptical and cylindrical holes with 90° compound angle

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Guohua Zhang ◽  
Gongnan Xie ◽  
Bengt Ake Sunden
Keyword(s):  
Film Cooling ◽  
Cross Sectional ◽  
Cooling Effectiveness ◽  
Content Type ◽  
Film Cooling Effectiveness ◽  
Cylindrical Model ◽  
Blowing Ratio ◽  
Elliptical Model ◽  
Lift Off ◽  
Compound Angle

Purpose In this study, numerical simulations are performed to compare the adiabatic film cooling effectiveness and reveal the difference of film cooling mechanisms of two models with the same geometries and cross-section areas of film holes’ exits at three typical blowing ratios (M = 0.5, 1 and 1.5). The two models are an elliptical model and a cylindrical model with 90° compound angle, respectively. Design/methodology/approach Three different cases are considered in this work and the baseline is the model with a cylindrical film hole. The same boundary conditions and a validated turbulence model (realizable k-ε) are adopted for all cases. Findings The results show that both the elliptical and cylindrical models with 90° compound angle can enhance the film cooling effectiveness compared with the baseline. However, the elliptical model performs well at lower blowing ratios and in the near region at each blowing ratio because of the wider width of the film hole’s exit. The cylindrical model with 90° compound angle provides better film cooling effectiveness in the further downstream area of the film hole at higher blowing ratio because of the less lift-off and better coolant coverage in the larger x/D region along the mainstream direction. Originality/value Overall, it can be concluded that although the elliptical and cylindrical models with 90° compound angle have identical hole exits, the different inlet direction and cross-sectional geometry affect the flow structures when the coolant enters, moves through and exits the hole and finally different film cooling results appear.

scholarly journals Effects of O2 Plasma Treatments on the Photolithographic Patterning of PEDOT:PSS

Coatings ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 31
Author(s):  
Deng-Yun Zheng ◽  
Meng-Hsiang Chang ◽  
Ci-Ling Pan ◽  
Masahito Oh-e
Keyword(s):  
Indium Tin Oxide ◽  
Spin Coating ◽  
Cross Sectional ◽  
Similar Treatment ◽  
Plasma Treatments ◽  
Mechanical Durability ◽  
Conformal Coverage ◽  
Conventional Photolithography ◽  
Lift Off ◽  
O2 Plasma

Poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) is known for its potential to replace indium–tin oxide in various devices. Herein, when fabricating finger-type PEDOT:PSS electrodes using conventional photolithography, the cross-sectional profiles of the patterns are U-shaped instead of rectangular. The films initially suffer from non-uniformity and fragility as well as defects owing to undesirable patterns. Adding a small amount of hydrolyzed silane crosslinker to PEDOT:PSS suspensions increases the mechanical durability of PEDOT:PSS patterns while lifting off the photoresist. To further improve their microfabrication, we observe the effects of two additional oxygen (O2) plasma treatments on conventional photolithography processes for patterning PEDOT:PSS, expecting to observe how O2 plasma increases the uniformity of the patterns and changes the thickness and U-shaped cross-sectional profiles of the patterns. Appropriately exposing the patterned photoresist to O2 plasma before spin-coating PEDOT:PSS improves the wettability of its surface, including its sidewalls, and a similar treatment before lifting off the photoresist helps partially remove the spin-coated PEDOT:PSS that impedes the lift-off process. These two additional processes enable fabricating more uniform, defect-free PEDOT:PSS patterns. Both increasing the wettability of the photoresist patters before spin-coating PEDOT:PSS and reducing its conformal coverage are key to improving the photolithographic microfabrication of PEDOT:PSS.

Grain Structure and Electromigration Testing of Deep Sub- Micrometer Cu Interconnects

1995 ◽  
Vol 391 ◽  
Author(s):  
Richard Frankovic ◽  
Gary H. Bernstein
Keyword(s):  
Electron Beam Lithography ◽  
Grain Structure ◽  
Al Alloy ◽  
Cross Sectional ◽  
Interconnect Test ◽  
Lifetime Testing ◽  
Electromigration Lifetime ◽  
Lift Off ◽  
Deposited Films

AbstractCopper interconnect test stripes were fabricated by electron-beam lithography, evaporation and lift-off to linewidths as small as 140 nm. Grain structure in the as-deposited films exhibited smaller standard deviation than long-term annealed films. Grain growth during the anneal step increased maximum grain size by 2.5 times. Electromigration lifetime testing indicated these interconnects have 2-4 orders-of-magnitude greater normal-use lifetimes than large cross-sectional area, large-grain Al-alloy interconnects.

scholarly journals Numerical Analysis of the Combustion Dynamics of Passively Controlled Jets Issuing from Polygonal Nozzles

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 554
Author(s):  
Łukasz Kuban ◽  
Jakub Stempka ◽  
Artur Tyliszczak
Keyword(s):  
Species Distributions ◽  
Reynolds Numbers ◽  
Mixing Rate ◽  
Cross Sectional ◽  
Combustion Dynamics ◽  
Average Temperature ◽  
Nozzle Shape ◽  
The Mean ◽  
Lift Off ◽  
The Impact

In the present work, the combustion of vitiated hydrogen jets issuing from differently shaped nozzles is modelled using the LES method. We investigate the impact of nozzle cross-sectional geometries (circular, square, triangular, hexagonal and hexagram) and the jet Reynolds numbers (Re= 18,000, 20,000 and 23,600) on the flame lift-off height, its structure, the locations of the temperature maxima and species distributions. The triangular nozzle yields the highest mixing rate and therefore the fastest decay of axial velocity and the fastest growth of the average temperature along the flame axis. It was found that for the largest Re, the zone of intense mixing and the reaction zone occur in distinct regions, while for the lower Re, these regions combine into an indistinguishable zone. Finally, it is shown that the lift-off height of the flames and the mean temperature field are non-linearly correlated with Re and strongly dependent on the nozzle shape.

Submicrometre lift-off line with T-shaped cross-sectional form

1981 ◽  
Vol 17 (12) ◽  
pp. 429 ◽  
Author(s):  
M. Matsumura ◽  
K. Tsutsui ◽  
Y. Naruke
Keyword(s):  
Cross Sectional ◽  
Lift Off

INVESTIGATIVE STUDY OF HEAT TRANSFER AND BLADES COOLING IN THE GAS TURBINE

2005 ◽  
Vol 19 (28n29) ◽  
pp. 1611-1614
Author(s):  
TECK SENG LOH ◽  
SUTTHIPHONG SRIGRAROM
Keyword(s):  
Heat Transfer ◽  
Cross Flow ◽  
Injection Technique ◽  
Water Tunnel ◽  
Sectional Area ◽  
Cross Sectional ◽  
Dye Release ◽  
Lift Off ◽  
Visualization Experiments ◽  
Flow Stream

Flow visualization experiments had been conducted using a water tunnel to investigate and study the effect of different hole geometries on lift-off and spreading characteristics on a jet in a cross flow stream. The relationships between the hydraulic diameters of the hole geometries and their lift-off and spreading characteristics were also investigated. Eight different hole geometries with the same cross-sectional area were used in the experiments. They are round, square, triangle, rectangular, "rect-circle", "peanut", "V-shaped" and "W-shaped". Dye release injection technique was used to visualize the characteristics of the jet trajectories from different hole geometries. From the results, the different geometries of cooling holes were found to have an effect on the trajectory of the jet. Hole geometries with "tongues" in them such as "W-shaped" and "V-shaped" holes produced jets with better flow adherence but poorer spreading. Hole geometries with lower hydraulic diameters also produced jets with better flow adherence but poorer spreading.

Automated Image Analysis Of Nuclear And Cytoplasmic Changes In Exfoliated Cells From Tracheas Treated With Carcinogen

1977 ◽  
Vol 35 ◽  
pp. 220-221
Author(s):  
S.F. Stinson ◽  
J.C. Lilga ◽  
M.B. Sporn
Keyword(s):  
Image Analysis ◽  
Pattern Analysis ◽  
Relative Proportion ◽  
Automated Image Analysis ◽  
Image Analyzer ◽  
Cross Sectional ◽  
Exfoliated Cells ◽  
Neoplastic Lesions ◽  
Analysis System ◽  
Morphologic Criterion

Increased nuclear size, resulting in an increase in the relative proportion of nuclear to cytoplasmic sizes, is an important morphologic criterion for the evaluation of neoplastic and pre-neoplastic cells. This paper describes investigations into the suitability of automated image analysis for quantitating changes in nuclear and cytoplasmic cross-sectional areas in exfoliated cells from tracheas treated with carcinogen.Neoplastic and pre-neoplastic lesions were induced in the tracheas of Syrian hamsters with the carcinogen N-methyl-N-nitrosourea. Cytology samples were collected intra-tracheally with a specially designed catheter (1) and stained by a modified Papanicolaou technique. Three cytology specimens were selected from animals with normal tracheas, 3 from animals with dysplastic changes, and 3 from animals with epidermoid carcinoma. One hundred randomly selected cells on each slide were analyzed with a Bausch and Lomb Pattern Analysis System automated image analyzer.

Sign in / Sign up

Export Citation Format

Share Document