Methodologies for Quantifying FIB “Milling Acuity”

2009 ◽  
Author(s):  
Chad Rue
Keyword(s):  
Aspect Ratio ◽  
Real World ◽  
High Aspect Ratio ◽  
Process Development ◽  
Spot Size ◽  
Performance Tests ◽  
Imaging Resolution ◽  
Measuring Scheme ◽  
Column Performance

Abstract FIB column performance can be difficult to evaluate, and the traditional metrics of imaging resolution and minimum spot size give little indication of how a FIB system will perform its intended daily tasks. A series of supplemental FIB performance tests is proposed to quantify “milling acuity” under real-world conditions. A quantitative measuring scheme for evaluating the quality of High Aspect Ratio (HAR) vias is proposed, and an example is shown in which the HAR measuring scheme can be used for process development.

scholarly journals Optical Detection Method for High Aspect Ratio Microstructures

Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 296
Author(s):  
Wenbin Wei ◽  
Shuangyue Hou ◽  
Zhao Wu ◽  
Yue Hu ◽  
Yi Wang ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Visible Light ◽  
High Aspect Ratio ◽  
Detection Method ◽  
Optical Detection ◽  
System Parameters ◽  
Efficient Detection ◽  
Reflection Of Light ◽  
Application Fields

High aspect ratio microstructures (HARMS) are of great importance for many application fields. Many defects are generated during the fabrication processes, especially in line microstructures, and it is necessary to examine the quality of the structures after each process. However, there is no suitable efficient nondestructive detection method to monitor microstructures during the fabrication processes. In this paper, an optical detection method capable of detecting the structures by analyzing the reflection of light on the line HARMS is proposed. According to the image of reflected visible light, this method can determine whether there are defects in structures, so as to realize efficient detection. Preliminary simulations and experiments have been performed to confirm the feasibility and validity of the proposed method for detecting line microstructures. This method is expected to obtain more information about microstructures by further optimizing system parameters.

scholarly journals Analysis of the impact of inhomogeneous emissions in a semi-parameterized street canyon model

2015 ◽  
Vol 8 (2) ◽  
pp. 935-977
Author(s):  
T.-B. Ottosen ◽  
K. E. Kakosimos ◽  
C. Johansson ◽  
O. Hertel ◽  
J. Brandt ◽  
...  
Keyword(s):  
Air Pollution ◽  
Aspect Ratio ◽  
Theoretical Calculation ◽  
Real World ◽  
High Aspect Ratio ◽  
Street Canyon ◽  
The Other ◽  
Width Ratio ◽  
Improved Performance ◽  
The Impact

Abstract. Semi-parameterized street canyon models, as e.g. the Operational Street Pollution Model (OSPM®), have been frequently applied for the last two decades to analyse levels and consequences of air pollution in streets. These models are popular due to their speed and low input requirements. One often used simplification is the assumption that emissions are homogeneously distributed in the entire length and width of the street canyon. It is thus the aim of the present study to analyse the impact of this assumption by implementing an inhomogeneous emission geometry scheme in OSPM. The homogeneous and the inhomogeneous emission geometry schemes are validated against two real-world cases: Hornsgatan, Stockholm, a sloping street canyon; and Jagtvej, Copenhagen; where the morning rush hour has more traffic on one lane compared to the other. The two cases are supplemented with a theoretical calculation of the impact of street aspect (height / width) ratio and emission inhomogeneity on the concentrations resulting from inhomogeneous emissions. The results show an improved performance for the inhomogeneous emission geometry over the homogeneous emission geometry. Moreover, it is shown that the impact of inhomogeneous emissions is largest for near-parallel wind directions and for high aspect ratio canyons. The results from the real-world cases are however confounded by challenges estimating the emissions accurately.

Proton Beam Nano-Machining: End Station Design and Testing

2003 ◽  
Vol 777 ◽  
Author(s):  
J.A. van Kan ◽  
A.A. Bettiol ◽  
F. Watt
Keyword(s):  
Aspect Ratio ◽  
Proton Beam ◽  
High Aspect Ratio ◽  
Ion Beam ◽  
Spot Size ◽  
High Energy ◽  
Direct Write ◽  
Proton Beam Energy ◽  
National University ◽  
Physics Department

AbstractA new nuclear nanoprobe facility has been developed at the Centre for Ion Beam Applications (CIBA) in the Physics Department of the National University of Singapore. This facility is the first of its type dedicated to proton beam micromachining on a micron as well as a nano scale. The design and performance of the facility, which is optimized for 3D lithography with MeV protons, is discussed here. The system has been designed to be compatible with Si wafers up to 6”.The production of good quality high aspect ratio microstructures requires a lithographic technique capable of producing microstructures with smooth vertical sidewalls. In proton beam micromachining, a high energy (e.g. 2 MeV) proton beam is focused to a sub-100 nm spot size and scanned over a resist material (e.g. SU-8 and polymethylmethacrylate (PMMA)). When a proton beam interacts with matter it follows an almost straight path, the depth of which is dependent on the proton beam energy. These features enable the production of nanometer sized polymer structures. Experiments have shown that post-bake and curing steps are not required in this SU-8 process, reducing the effects of cracking and internal stress in the resist. Since proton beam micromachining is a fast direct write lithographic technique it has high potential for the production of high-aspect-ratio nano-structures.

Sign in / Sign up

Export Citation Format

Share Document