Electrodeposited Metal Structures in High Aspect Ratio Cavities using Vapor Deposited Polymer Molds and Laser Micromachining

2007 ◽  
Author(s):  
F. Herrault ◽  
C.-H. Ji ◽  
S. Rajaraman ◽  
R.H. Shafer ◽  
M.G. Allen
Keyword(s):  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Laser Micromachining ◽  
Metal Structures ◽  
Electrodeposited Metal

Laser micromachining and nickel plating of high-aspect-ratio structures in polymer molds

2001 ◽  
Author(s):  
Hengyi Jin ◽  
Muralihar K. Ghantasala ◽  
Jason P. Hayes ◽  
Karlo Jolic ◽  
Erol C. Harvey
Keyword(s):  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Laser Micromachining ◽  
Nickel Plating

scholarly journals Optimization of femtosecond laser cutting of biodegradable polymer for medical devices manufacturing

2016 ◽  
Vol 8 (4) ◽  
pp. 116 ◽  
Author(s):  
Bogusz Stepak ◽  
Arkadiusz J. Antonczak ◽  
Krzysztof M. Abramski
Keyword(s):  
Aspect Ratio ◽  
Femtosecond Laser ◽  
Medical Devices ◽  
Biodegradable Polymer ◽  
High Aspect Ratio ◽  
Laser Cutting ◽  
Laser Micromachining ◽  
Scanning Strategy ◽  
Vascular Stents ◽  
Femtosecond Laser Micromachining

This paper describes the experimental parameters involved in the femtosecond laser micromachining of biodegradable poly(L-lactide) which is frequently used in biomedical applications such as vascular stents or scaffolds. We investigated the influence of laser pulse energy, scanning strategy and number of overscans on the laser cutting throughput. The process parameters that enable reducing of a heat affected zone were determined. As a result, the optimal scanning strategy was determined in order to obtain high aspect ratio trenches in 380 ?m thick biodegradable polymer sheet. Full Text: PDF ReferencesW. Jia et al. "Effects of high-repetition-rate femtosecond laser micromachining on the physical and chemical properties of polylactide (PLA)", Opt. Express 23, 21 (2015). CrossRef F. Hendricks, R. Patel, and V.V. Matylistsky, "Micromachining of bio-absorbable stents with ultra-short pulse lasers", Proc. SPIE 9355, 935502 (2015). CrossRef W.Y. Yeong et al. "Annealing of Biodegradable Polymer Induced by Femtosecond Laser Micromachining", Adv. Eng. Mater. 4, 12 (2010). CrossRef K. Stolberg et al. "IR and green femtosecond laser machining of heat sensitive materials for medical devices at micrometer scale", Proc. SPIE 8968, 89680E (2014). CrossRef F. Hendricks et al. "High aspect ratio microstructuring of transparent dielectrics using femtosecond laser pulses: method for optimization of the machining throughput", Appl. Phys. A 117, 1 (2014). CrossRef A. Antonczak et al. "Degradation of poly(l-lactide) under CO2 laser treatment above the ablation threshold", Polym. Deg. Stab. 109, 97-105 (2014) CrossRef B. Stepak et al. "The influence of ArF excimer laser micromachining on physicochemical properties of bioresorbable poly(L-lactide)", Proc SPIE 9736, 97361T (2016). CrossRef

Development of LIGA-Like Process With Positive Photoresist and SU-8

2010 ◽  
Author(s):  
Yongsu Lee ◽  
Jinha Kim ◽  
Seokwoo Lee ◽  
Seungsub Lee
Keyword(s):  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Spin Coating ◽  
Atmospheric Condition ◽  
Metal Structures ◽  
Positive Photoresist ◽  
Dry Process ◽  
Aspect Ratios ◽  
Thick Photoresist ◽  
Photolithography Process

LIGA-Like techniques allows the fabrication of structures with high aspect ratio. SU-8 is a well-known thick photoresist used in this process. However, the remainder of highly cross-linked epoxy after photolithography process is difficult to remove without damage or alteration to electroplated metal due to the high aspect ratio of the structure. Different from SU-8, positive photoresist is easily removed, yet has limitation of fabricating structures with high aspect ratio. In this paper, we present novel LIGA-Like process with positive photoresist to improve above mentioned difficulties. In order to increase a height of positive photoresist, we have introduced SU-8 into the system. SU-8 is used for cast to control the thickness of positive photoresist, and AZ9260 (positive photoresis) is used for electroplating mold. In this suggested process, Donut-shaped SU-8 cast is patterned on the border of substrate to control and increase total height of positive photoresist. AZ9260, a kind of positive photoresist, fills the center of vacant area, and the thickness of the AZ9260 is controlled by height of SU-8 cast during the process of slow spin coating. After spin coating, the system is exposed to natural atmospheric condition for hours to improve surface planarization. The soft baking is carried out in two steps. The purpose of first prebaking is to evaporate large amount of solvent, and second prebaking is to enhance aspect ratios of photoresist. In the process of prebaking, the AZ9260 coated wafer is covered with chalet due to the fast dry process causes wrinkle and bubble on the surface. Through extensive experiments, we have established the condition of spin coating, exposure doses, prebaking and development process in each structure of 150, 200 and 240 μm thickness. Different from the case of SU-8, AZ9260 mold can be effectively removed after electroplating treatment. Finally, we obtain metal structures of 150, 200, 240μm heights corresponding to the mold height (AZ9260). It is shown that SU-8 can be successfully replaced by positive photoresist in LIGA-Like process. Therefore, the suggested fabrication method can be applied to materialize the positive photoresist structures with high aspect ratio in UV lithography process.

Laminated Photoresist Sacrificial Layer Process for 3-D Movable Suspension Microstructures in LIGA-Based Surface Micromachining

2010 ◽  
Vol 97-101 ◽  
pp. 2538-2541 ◽  
Author(s):  
Yi Bo Wu ◽  
Gui Fu Ding ◽  
Cong Chun Zhang ◽  
Hong Wang
Keyword(s):  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Sacrificial Layer ◽  
Low Cost ◽  
Three Dimensional ◽  
Mems Devices ◽  
Metal Structures ◽  
Positive Photoresist ◽  
Out Of Plane ◽  
Freely Moving

The fabrication process of three-dimensional (3D) high-aspect-ratio MEMS devices entirely made of electroplated metals with suspending multilayered microstructures is reported. The technology used is a LIGA-liked micromachining process, called the laminated positive photoresist sacrificial layer process (LPSLP). The LPSLP allows in UV-lithography not only for thick resist mould for electroplating of cascaded metal structures but also for the sacrificial layer for supporting mechanically the suspensions. So far the LPSLP procedure has incorporated with more than five sacrificial layers, which allows for the creation of overhanging structures and freely moving parts like out-of-plane cantilever stacks. A description of the underlying fabrication principle and processing details is discussed in this paper. Thus the proposed procedures open a low-cost route for fabricating micro-components such as cantilevers, bridges, movable electrodes, and freestanding parts.

Sign in / Sign up

Export Citation Format

Share Document