New CD-SEM metrology method for the side wall angle measurement using multiple detectors

Due to the trend of miniaturization on electrical devices, medical devices, and energy, etc., the need for micro and mini metal parts is increasing at a tremendous rate. In order to realize the potential of the mini-parts and take advantages from the mini-forming process, innovative modifications of the forming process must be developed. These modifications are particularly important with respect to the mini-parts forming, which offers an excellent opportunity to produce high accurate mini parts and to reduce manufacturing costs and time. However, severe modifications of the material thickness occur during forming of mini-parts. This paper presents a study concerning the material thickness variation during forming process of mini-parts. The main objective is to understand the material behaviour during forming of mini-parts. The material used in this analysis is copper - zinc alloy with anisotropic properties. During forming process of conical mini-parts, the material become very thin around the punch radius and become thicker at the upper end of the part. This phenomenon cause forming problems such: material fracture, wrinkling, part diameter variation, springback etc. There are multiple factors that affect the material thickness variation during forming process as: side wall angle, friction coefficient, punch radius, and punch speed. The Dynaform 5.9.1 software was used to simulate the forming process. The part obtained after each simulation was analyzed and measured to quantify material thickness variation on the final conical mini-part. To analyze the behaviour of the material during deep drawing process the obtained results for different conical mini-parts were compared. In the final part of this paper some conclusions regarding the material thickness variation during forming of conical mini-parts are presented.

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Spatial mode projection for side-wall angle measurements

10.1117/12.2184738 ◽

2015 ◽

Author(s):

L. Cisotto ◽

Yan Zhu ◽

S. F. Pereira ◽

H. P. Urbach

Keyword(s):

Side Wall ◽

Spatial Mode ◽

Wall Angle ◽

Angle Measurements

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Thick photosensitive polyimide film side wall angle variability and scum improvement for IC packaging stress control

Advances in Patterning Materials and Processes XXXV ◽

10.1117/12.2297360 ◽

2018 ◽

Author(s):

Premachandran CS ◽

Danish Faruqui ◽

Sohan S. Mehta ◽

Marco Yeung ◽

Fahad Mirza ◽

...

Keyword(s):

Side Wall ◽

Polyimide Film ◽

Wall Angle ◽

Stress Control ◽

Ic Packaging ◽

Film Side

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The moisture-dependent flow characteristics of Canarium schweinfurthii Engler nuts

Research in Agricultural Engineering ◽

10.17221/47/2018-rae ◽

2019 ◽

Vol 65 (No. 2) ◽

pp. 40-47

Author(s):

James Chinaka Ehiem ◽

Victor Ifeanyichukwu Obiora Ndirika ◽

Udochukwu Nelson Onwuka ◽

Vijaya Raghavan

Keyword(s):

Shear Stress ◽

Shear Force ◽

Flow Characteristics ◽

Side Wall ◽

Flow Properties ◽

Wall Angle ◽

Universal Machine ◽

Smooth Flow ◽

Dependent Flow ◽

And Storage

The flow characteristics of three varieties of Canarium schweinfurthii Engler nuts (Canarium schweinfurthii short, Canarium schweinfurthii long and Canarium schweinfurthii large – CSHTLRG) relevant for the design and development of handling and storage systems was studied at three different moisture levels (10.20, 17.23 and 25.06% wet basis). The flow characteristics investigated include the normal stress, the shear stress, the initial shear stress, the coefficient and angle of the internal friction, the coefficient of mobility and the size of the discharge opening. An Instron universal machine at a cross-head speed of 25 mm·min–1 was used to obtain the shear force. The results obtained showed that all the flow properties increased with an increase in the moisture content except for the coefficient of mobility. Moreover, the variety of the C. schweinfurthii nuts had a significant effect (P < 0.05) on the flow characteristics. CSHTLRG had the best ability to flow freely than the other varieties. The hopper side wall angle for all the varieties ranged from 67–70°. Round, square and triangle shapes are all acceptable for the smooth flow of C. schweinfurthii nuts.

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Numerical Analysis of the Residual Stresses Caused by Forming Process in Case of Conical Mini-Parts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1036.269 ◽

2014 ◽

Vol 1036 ◽

pp. 269-273

Author(s):

Robert Stefanut Teaca ◽

Gheorghe Brabie

Keyword(s):

Residual Stresses ◽

Deep Drawing ◽

Side Wall ◽

Zinc Alloy ◽

Forming Process ◽

Wall Angle ◽

Cold Forming ◽

Copper Zinc ◽

Dimensional Errors ◽

Forming Tools

The research presented in this paper refers to numerical simulation related to deep drawing of conical mini-parts having different geometries as a function of side wall angle. The mini-parts are made from copper zinc alloy, having the thickness of 0.2 mm. Very important concerns in cold forming of conical mini-parts are the residual stresses due to their influence on the final shape of the part. During the forming process, due to different angles of the side wall, the residual stresses vary. After the mini-part is removed from the forming tools, the residual stresses modify the geometry of the part, causing dimensional errors. The residual stresses decrease the ability of the designer to draw some specific shapes because it may create forming problems such as wrinkling, tearing, and uncontrollable springback. The Dynaform 5.9.1 software was used to simulate the forming process. The part obtained after each simulation was analyzed and measured to quantify the effect of the residual stresses on the final geometry of part. All the parameters were maintained constant excepting the side wall angle. The obtained results for different side wall angles were compared to realize the behaviour of the conical mini-parts during and after deep drawing process.

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Waveguide side-wall angle dependant resonance of a Si micro ring-resonator

10.1109/cleopr.2015.7376045 ◽

2015 ◽

Author(s):

M. Rakib Uddin ◽

Nur'Azmina Lingas ◽

Bikash Nakarmi ◽

Yong Hyub Won

Keyword(s):

Ring Resonator ◽

Side Wall ◽

Wall Angle

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