共查询到20条相似文献,搜索用时 31 毫秒
1.
Rahul Shukla V. P. Dhamgaye V. K. Jain P. Ram Sankar C. Mukherjee B. D. Pant G. S. Lodha 《Microsystem Technologies》2014,20(7):1273-1280
We report microfabrication of high aspect ratio comb-drive using deep X-ray lithography at Indus-2 synchrotron radiation source. Analysis shows that the comb-drive actuator of aspect ratio 32 will produce nearly 2.5 μm displacement when 100 V DC is applied. The displacement increases as the gap between the comb finger decreases. For fabrication of comb-drive, polyimide–gold X-ray mask using UV lithography is made for the first time in India. To pattern on an 800 μm thick X-ray photoresist (PMMA) exposures are performed using our deep X-ray lithography beamline (BL-07) at Indus-2. Metallization on the selective regions of the developed X-ray photoresist with comb-drive pattern was carried out by RF sputtering. Following this the comb-drive actuator of PMMA was fabricated by one-step X-ray lithography. The comb-drive can also be used as a sensor, energy harvester, resonator and filter. 相似文献
2.
Quasi-three-dimensional (3D) microstructure fabrication technique utilizing hard X-ray lithography (HXL) has been developed.
In this technique, as the intensity distribution of the X-rays is controlled by a newly developed bending mirror, the exposure
residual depth of polymethyl methacrylate (PMMA) resist is controlled over the exposed area. The maximum difference of depths
was approximately 50 μm over the large area more than 60 mm (horizontal) × 5 mm (vertical). We also investigated the effects
of controlling the beam intensity distribution for exposure changing X-ray mask absorber shapes and angle on the obtained
quasi-3D resist pattern shapes. As the results, Quasi-3D PMMA patterns with inclined shape sidewall and graded depths were
successfully fabricated. We believe this technique greatly expands applications of LIGA process.
Received: 10 August 2001/Accepted: 24 September 2001
This paper was presented at the Fourth International Workshop on High Aspect Ratio Microstructure Technology HARMST 2001
in June 2001. 相似文献
3.
Sven Achenbach David Klymyshyn Darcy Haluzan Timo Mappes Garth Wells Jürgen Mohr 《Microsystem Technologies》2007,13(3-4):343-347
Radio frequency micro electro-mechanical systems (RF MEMS) vertical cantilever variable capacitors fabricated using deep X-ray
lithography and electroplating are presented. Polymethylmethacrylate (PMMA) layers of 100 μm and 150 μm have been patterned
and electroplated with 70 μm and 100 μm thick nickel. A 3 μm thick titanium layer was used as plating base as well as etch
time-controlled sacrificial layer for the release of the cantilever beam. The parallel plate layout includes narrow gaps and
cantilever beams with an aspect ratio in nickel of up to 60 for 1 mm long features. Auxiliary structures support the beams
and gaps during the processing. Room temperature electroplating significantly reduces the risk of deformations compared to
the standard process temperature of 52°C. The capacitors operate in the 1–5 GHz range, and demonstrate good RF performance,
with quality factors on the order of 170 at 1 GHz for a 1 pF capacitance. 相似文献
4.
Isao Kobayashi Sayumi Hirose Takanori Katoh Yanping Zhang Kunihiko Uemura Mitsutoshi Nakajima 《Microsystem Technologies》2008,14(9-11):1349-1357
Microchannel (MC) emulsification is a promising technique for producing monodisperse emulsions consisting of highly uniform droplets. The authors developed a high-aspect-ratio microstructure (HARMST) made of poly(methyl methacrylate) (PMMA) as a new MC emulsification device. A PMMA straight-through MC array plate consisting of 31,250 through-holes with a 7.3 × 22.9-μm oblong section and a 200-μm depth was fabricated by a process of synchrotron radiation (SR) lithography and etching. Oblong MCs fabricated in a PMMA straight-through MC array were highly uniform with a coefficient of variation of less than 2%. The fabricated PMMA straight-through MC array plate was used to produce water-in-oil (W/O) emulsions. Monodisperse W/O emulsions with average droplet diameters of approximately 25 μm and a minimum coefficient of variation of 3.2% were produced via a hydrophobic PMMA straight-through MC array. The PMMA straight-through MC array plate also produced monodisperse W/O emulsions at droplet production rates of up to 1.7 × 104/s. The PMMA straight-through MC array plates developed in this work are expected to expand the application field of emulsification using straight-through MC array plates, which have previously been made of single-crystal silicon. 相似文献
5.
Submicron-scale surface acoustic wave resonators fabricated by high aspect ratio X-ray lithography and aluminum lift-off 总被引:1,自引:0,他引:1
Sven Achenbach David Klymyshyn Timo Mappes Anton Kachayev Venkat Subramanian Garth Wells Jürgen Mohr 《Microsystem Technologies》2008,14(9-11):1715-1719
A submicron-scale surface acoustic wave (SAW) resonator fabricated by high-aspect-ratio X-ray lithography (XRL) and metal lift-off that operates at microwave frequencies is presented. We demonstrate that XRL is especially well suited for SAW device templating, as long submicron-scale interdigitated transducer structures can be batch patterned with excellent structure quality. 0.4–2.0 μm thick PMMA layers were structured by X-ray lithography shadow projection using silicon nitride-based X-ray masks. Structures with a critical lateral feature size of down to 200–700 nm were processed. The polymer structures served as templates in a subsequent aluminum lift-off process. The metal electrodes were successfully tested as SAW resonators for high frequency applications, e.g. around 1.3 GHz, using calibrated 1-port RF wafer probing measurements. Compared with standard fabrication techniques, the high structure quality of submicron-scale polymer templates made of unusually thick PMMA layers offers additional possibilities to fabricate thicker metal transducers. 相似文献
6.
Tao Wang McCandless A.B. Lienau R.M. Kelly K.W. Hensley D. Desta Y. Zhong-Geng Ling 《Journal of microelectromechanical systems》2005,14(2):400-409
This paper describes a process to fabricate monolithic multilevel high-aspect-ratio microstructures (HARMs) for ferromagnetic devices built on silicon wafers using aligned X-ray lithography in conjunction with electrodeposition. Two X-ray masks were fabricated, each consisting of gold (Au) absorber structures on a transparent polyimide membrane. One mask was used to print a polymethyl methacrylate (PMMA) resist layer. Then, a second PMMA layer was applied to the same wafer, and the second mask was used to pattern it. Transparent alignment windows in the second mask, combined with a piezoelectrically controlled X-ray aligner, allowed for high alignment accuracy between the two print patterns over large areas (>4 inch in diameter). Au circuits were electroplated into first PMMA layer from a sulfite-based electrolyte, and nickel-iron (NiFe) ferromagnetic HARMs were formed in second PMMA resist from a sulfate-based bath. The deposition resulted in well-defined NiFe structures with aspect-ratios up to 67:1 as well as smooth sidewalls and top surfaces. Chemical composition measurements with energy X-ray dispersive spectroscopy (EDS) and wavelength X-ray dispersive spectroscopy (WDS) showed that Fe content increased during the electrodeposition process. To electrically isolate the NiFe posts and Au circuits, both wet chemical etching and sputter etching were explored to remove the exposed seed layer, and the latter approach completely removed the seed layers without damaging the electroplated features. 相似文献
7.
N. Moldovan D. C. Mancini R. Divan O. V. Makarova A. Peele K. R. Podolak 《Microsystem Technologies》2002,9(1-2):130-132
An experimental characterization of the roughness of side walls in ultradeep, hard X-ray lithography was performed. Several
sources of roughness were distinguished: the roughness of the absorber layer on the mask, the roughness of the mask substrate,
nonhomogeneities in the X-ray beam, incomplete developing, cracks generated in the PMMA, and the thermal treatment of PMMA.
The intrinsic roughness of the correctly developed PMMA was estimated to about 4 nm rms. The best results showed an anisotropy
of roughness with minimal values of 4 nm rms along the Oz direction (parallel with the X-ray beam) and 25 nm rms in the Ox direction.
Received: 10 August 2001/Accepted: 24 September 2001
This work is supported by the U.S. Department of Energy, Office of Science, under Contract No. W-31-109-ENG-38.
This paper was presented at the Fourth International Workshop on High Aspect Ratio Microstructure Technology HARMST 2001
in June 2001. 相似文献
8.
9.
Sven Achenbach Martin Boerner Seichin Kinuta Walter Bacher Juergen Mohr Volker Saile Yasunori Saotome 《Microsystem Technologies》2007,13(3-4):349-353
The structure quality of deep X-ray lithography components strongly depends on the quality of the applied X-ray mask. In this
article we compare the results obtained with two different mask types. Sophisticated working masks generated by e-beam lithography,
soft X-ray lithography and electroplating of gold absorbers on a titanium mask membrane have been fabricated at the Institute
for Microstructure Technology, Research Center, Karlsruhe (FZK/IMT), Germany. Prototype masks generated by e-beam lithography,
optical lithography and electroplating of gold absorbers on a polyimide mask membrane have been fabricated by Optnics Precision,
Japan, with the aim to offer commercially available low cost masks. Both mask types were applied to pattern PMMA resist layers
of 300–750 μm thickness at the 2.5 GeV electron storage ring ANKA, Germany, using comparable process parameters. FZK/IMT masks
provide microstructures with significantly better structure quality. The layout area, however, is currently limited to 12 cm2, and the Ti mask membrane tends to lead to a slight resist surface attack, such as rounding of the resist edges. Optnics
masks provide microstructures with reduced structure quality due to sidewall striations (sidewall roughness up to 2 μm) and
thermal distortions (of up to 3–5 μm) which limit the potential scope of applications. They could nevertheless potentially
be applied as low quality, low cost X-ray masks. High resolution and high accuracy applications, however, require more sophisticated
but also more expensive masks, like the Ti-masks from FZK/IMT. 相似文献
10.
Fabrication techniques of microstructures with high resolution and high aspect ratio are necessary for practical microelectromechanical
systems (MEMS) that have high performance and integration. In order to fabricate microstructures with sub-micron resolution
and high aspect ratio, deep X-ray lithography has been investigated using the compact synchrotron radiation (SR) light source
called “AURORA”. An X-ray mask for sub-micron deep X-ray lithography, which is composed of 1 μm thick Au as absorbers, 2 μm
thick SiC as a membrane and 625 μm thick Si as a frame, was designed. In preliminary experiments, the following results were
achieved: EB resist microstructures with an aspect ratio of 22 corresponding with 0.07 μm width and 1.3 μm height were formed;
a 10 μm thick PMMA resist containing no warp was formed by direct polymerization, enabling more precise gap control. 相似文献
11.
In the first step of the LIGA process microstructures with high aspect ratios are fabricated by patterning a resist layer
with deep etch X-ray lithography. As resist typically PMMA (polymethylmethacrylate) is used. For the following electroforming
process and to achieve perfect microstructures the adhesion of the PMMA on the substrates is of great importance.
For a better understanding the adhesion mechanism, particular induced through the adhesion promoter MEMO (methacryloxypropyl-trimethoxysilane)
was investigated on various substrates. Two methods, namely XANES/EXAFS spectroscopy under grazing incidence and shear stress
measurements were modified for the specific needs of microstructures.
Our studies proved that the adhesion strength is determined by two factors.
A rough surface, which allows mechanical interlocking, increases the adhesion strength by about 10%. The larger part of the
adhesion strength is determined by formation of chemical bonds when adding an adhesion promoter. E.g. addition of 5% adhesion
promoter increases the adhesion strength by 90%. These results were, as far as possible, confirmed by the X-ray spectroscopical
measurements. 相似文献
12.
A. G. Peele K. D. Vora B.-Y. Shew B. Loechl E. C. Harvey J. P. Hayes 《Microsystem Technologies》2007,13(5-6):511-515
We have previously considered some of the parameters for, and production issues involved in making, a useful Lobster-eye prototype
using X-ray lithography. Due to the high aspect ratio and dense packing of the array features, we were unable, in our initial
attempts to produce optimal Lobster-eye optics using X-ray lithography and a PMMA resist, to consistently overcome adhesion
issues between the substrate and the resist. In recent work we have overcome this problem by using SU-8 as the resist instead.
In the light of this advance we reconsider the relevant parameters and production issues when using SU-8 and lower-energy
exposures. 相似文献
13.
Zongbo Zhang Yi Luo Xiaodong Wang Yingsong Zheng Yanguo Zhang Liding Wang 《Microsystem Technologies》2010,16(4):533-541
Bonding is a bottleneck for mass-production of polymer microfluidic devices. A novel ultrasonic bonding method for rapid and
deformation-free bonding of polymethyl methacrylate (PMMA) microfluidic chips is presented in this paper. Convex structures,
usually named energy director in ultrasonic welding, were designed and fabricated around micro-channels and reservoirs on
the substrates. Under low amplitude ultrasonic vibration, localized heating was generated only on the interface between energy
director and cover plate, with peak temperature lower than T
g (glass transition temperature) of PMMA. With the increasing of temperature, solution of PMMA in isopropanol (IPA) increases
and bonding was realized between the contacting surfaces of energy director and cover plate while no solution occurs on the
surfaces of other part as their lower temperature. PMMA microfluidic chips with micro-channels of 80 μm × 80 μm were successfully
bonded with high strength and low dimension loss using this method. 相似文献
14.
O. Tabata H. You N. Matsuzuka T. Yamaji S. Uemura I. Dama 《Microsystem Technologies》2002,8(2-3):93-98
Based on a moving mask deep X-ray lithography concept, a new deep X-ray exposure system with multi stage has been built up,
which can fabricate 3 dimensional microstructures with controllable free shaped wall such as inclined, curved and vertical
wall. The system has 6 stages, an X-stage and a Y-stage for substrate scanning, a substrate tilt stage and a substrate rotation stage for controlling an incident X-ray angle
to a substrate, an X–Y stage for mask movement and X–Y stage for substrate and mask alignment. The system performance has been confirmed by fabricating microstructures such as
gratings, micro grid and micro prism.
Received: 10 August 2001/Accepted: 24 September 2001 相似文献
15.
Anja Voigt Marina Heinrich Gabi Gruetzner Josef Kouba H.-U. Scheunemann I. Rudolph 《Microsystem Technologies》2008,14(9-11):1447-1450
LIGA is a well-established process to fabricate metallic micro parts with high resolution, high precision and very low sidewall roughness by means of X-ray lithography and electroplating. The availability of a precise X-ray mask is a precondition for the final precision of the manufactured micro parts. Typical mask substrate materials, e.g. beryllium, carbon based foils, Si3N4 or SiC show different disadvantages such as low X-ray transparency or high toxicity or high prices or low conductivity or high thermal expansion or surface porosity causing X-ray scattering. For the fabrication of X-ray masks, PMMA with its unique features such as high aspect ratio patterns with high precision, exhibits low sensitivity and the layers preparation is not easy. SU-8, an epoxy-based UV and X-ray sensitive, chemically amplified, negative tone photoresist exhibits high aspect ratio patterns with vertical sidewalls. The difficult remove of the resist after the electroplating process significantly hinders the inspection of the fabricated X-ray mask. We present the use and suitability of an UV sensitive, chemically amplified, viscous, aqueous-alkaline developable, and easy removable positive tone photoresist, XP mr-P 15 AV, exhibiting high aspect ratio patterns with vertical sidewalls for the fabrication of X-ray masks by means of UV lithography on vitreous carbon substrates. 相似文献
16.
In the first step of the LIGA process microstructures with high aspect ratios are fabricated by patterning a resist layer
with deep etch X-ray lithography. As resist typically PMMA (polymethylmethacrylate) is used. For the following electroforming
process and to achieve perfect microstructures the adhesion of the PMMA on the substrates is of great importance.
For a better understanding the adhesion mechanism, particular induced through the adhesion promoter MEMO (methacryloxypropyl-trimethoxysilane)
was investigated on various substrates. Two methods, namely XANES/EXAFS spectroscopy under grazing incidence and shear stress
measuremsents were modified for the specific needs of microstructures.
Our studies proved that the adhesion strength is determined by two factors.
A rough surface, which allows mechanical interlocking, increases the adhesion strength by about 10%. The larger part of the
adhesion strength is determined by formation of chemical bonds when adding an adhesion promoter. E.g. addition of 5% adhesion
promoter increases the adhesion strnegth by 90%. These results were, as far as possible, confirmed by the X-ray spectroscopical
measurements.
The financial support of this project by the Federal Ministry of Science and Technology (contract No. 05 5P DAX18) is gratefully
acknowledged. 相似文献
17.
Timo Mappes Matthias Worgull Mathias Heckele Jürgen Mohr 《Microsystem Technologies》2008,14(9-11):1721-1725
This article describes the process chain for replication of submicron structures with varying aspect ratios (AR) up to 6 in polymethylmethacrylate (PMMA) by hot embossing to show the capability of the entire LIGA process to fabricate structures with these dimensions. Therefore a 4.7 μm thick layer of MicroChem 950k PMMA A11 resist was spin-coated on a 2.3 μm Ti/TiO x membrane. It was patterned with X-ray lithography at the electron storage ring ANKA (2.5 GeV and λ c ≈ 0.4 nm) at a dose of 4 kJ/cm3 using a Si3N4 membrane mask with 2 μm thick gold-absorbers. The samples were developed in GG/BDG and resulted in AR of 6–14. Subsequent nickel plating at 52°C resulted in a 200 μm thick nickel tool of 100 mm diameter, which was used to replicate slit-nozzles and columns in PMMA. Closely packed submicron cavities with AR 6 in the nickel shim were filled to 60% during hot embossing. 相似文献
18.
A. Schneider B. Su T. W. Button L. Singleton O. Wilhelmi S. E. Huq P. D. Prewett R. A. Lawes 《Microsystem Technologies》2002,8(2-3):88-92
In this paper results are presented from a range of experiments to explore the feasibility of inserting a ceramic material
PZT (lead zirconium titanate) into different kinds of high-aspect-ratio resist moulds. Polymethylmethacrylate (PMMA) and SU-8
on silicon substrates and free-standing SU-8 membranes with micro-cavities or through-holes (defined by X-ray lithography)
have been used as moulding medium. Processing conditions for the resist materials including pre-bake, exposure, post-bake,
development and stripping have been compared. The advantages of different types of resist mould for the LIGA process has been
evaluated. Additionally a comparison of photosensitivity of PMMA and SU-8 has been carried out. Using a range of load pressures
(5 to 60 MPa), appropriate conditions for PZT embossing into resist moulds have been determined (ensuring minimum void formation
in the final PZT structures). In the final form, SU-8 moulds have been removed by laser ablation. This is the first reporting
of high-aspect-ratio ceramic microstructures fabricated using a combination of SU-8 moulds and PZT embossing.
Received: 10 August 2001/Accepted: 24 September 2001 相似文献
19.
This paper describes the fabrication of poly(methyl methacrylate) (PMMA) microstructures with three-dimensional (3-D) sloped sidewalls using synchrotron-radiated (SR) deep X-ray lithography (DXRL). Here, the developer temperature was varied to produce variations in the inclination angle of the sloped sidewalls. We found that the PMMA sidewall inclination angle and height were controlled by the dosage, development time, and development temperature. When the development temperature was low, the inclination angle was nearly 0°, regardless of dosage amounts or exposure time. When the development temperature was high, microstructures with sloped sidewalls were fabricated; as the dosage amount and development time increased, the inclination angle increased. The ability to control the PMMA sidewall inclination angle suggests the application of this technique to microstructure fabrication technologies, such as 3-D microelectromechanical system (MEMS) device components, in which the inclination angle becomes the draft angle for moulding processes. 相似文献
20.
In this paper, the fabrication technique for high-aspect-ratio diffractive optical element (DOE) is introduced. The 500 nm-width
and 1,000 nm-width line-and-space pattern has been successfully fabricated. It was fabricated by synchrotron radiation (SR)
lithography for the application of nano gratings, and poly-methylmethacrylate (PMMA) was used as X-ray resist. The nanoscale
grating with the aspect ratio of 4.4 and 2.2 was achieved. So far, there are a number of reported techniques for fabrication
of DOEs yet the height of those gratings is not sufficient. Therefore, we have attempted to investigate the fabrication of
high-aspect-ratio nano gratings by a high-resolution X-ray lithography using SR source at Ritsumeikan University, Japan. Nevertheless,
the evaluation of various factors influencing the high-aspect-ratio structure fabricated by our recommended technique is discussed.
So far the fabricating process, such as, proximity gap of exposure, the exposure dosage, and the development time have been
optimized to fabricate the gratings. 相似文献