Mother Mold Research Articles

Use the 3D Printer Technology to Obtain Molds for Ceramic Products

Use the 3D printer technology to obtain molds for ceramic products Abstract: The research deals with the possibility of using 3d printers to obtain the mother mold of the ceramic product through a study of the 3d printing techniques and their types and raw materials used in printing with these printers and traditional methods for producing such kind of molds, and then the researcher reached to obtain a mother mold for the ceramic product using a 3d printer And computer-aided design (CAD) to prepare modeling and molds. Use the 3D printer technology to obtain molds for ceramic products Abstract: The research deals with the possibility of using 3d printers to obtain the mother mold of the ceramic product through a study of the 3d printing techniques and their types and raw materials used in printing with these printers and traditional methods for producing such kind of molds, and then the researcher reached to obtain a mother mold for the ceramic product using a 3d printer And computer-aided design (CAD) to prepare modeling and molds.

Efficient fabrication process for metallic structures of submicrometer size

This paper presents a new efficient, inexpensive fabrication process for metallic structures of submicrometer size scale. The process combines nanomachining and cold-welding transfer printing. Nanomachining is utilized to fabricate a Ni-P mother mold with designed pattern. The mother mold pattern is replicated to a PMMA stamp. After depositing an Au thin film on the surface of the PMMA stamp, the stamp is used to transfer print Au micro/nano structures onto a quartz substrate also deposited with a thin Au film. The adhesion mechanism is called cold-welding, based on avalanche adhesion between two metallic surfaces. A 5 mm * 2.1 mm area Au nanograting pattern is used as a test pattern. The pitch size of the pattern is 700 nm.

Efficient Fabrication Process of Metal Nanodot Arrays Using Direct Nanoimprinting Method with a Polymer Mold

A new fabrication process of metal nanodot arrays using the thermal dewetting method was developed in this study. This process was comprised of three steps: thin Au film deposition on a quartz glass substrate, groove patterning by direct nanoimprinting, and self-organization of metal nanodot arrays by thermal dewetting. A new idea to utilize a polymer film mold for groove patterning by direct nanoimprinting was examined. The polymer film mold was prepared by hot-embossing groove patterns of a mother mold on a cyclo olefin polymer (COP) film. The mother mold was prepared from a silicon wafer. The polymer film mold was used for direct nanoimprinting on a metal film deposited on a quartz substrate. The experimental results revealed that the COP film mold can effectively form a micro groove pattern on the Au film despite the COP film mold being softer than the Au film. The micro groove on the Au film was also found to be effective in aligning the nanodots in lines. The micro groove patterning using the COP film mold was also confirmed to be useful in controlling the dot size and alignment during the thermal dewetting process.

Replication of rose petal surfaces using a nickel electroforming process and UV nanoimprint lithography

In this research, we replicate the hierarchical structures of rose petals by using poly urethane acrylate (PUA) nanomolding technology. After a molding process, we use a PUA replica as the mother mold for nickel electroforming processes. By replicating the original rose petal hierarchical structure, we obtain the rose petal effect with nickel substrates. In order to make a negative-patterned nickel stamp, a second PUA replication was done using the first PUA mother mold and a nickel electroforming process was performed. Using these, the hierarchical structure of rose petals was imprinted in perfluoropolyether (PFPE), which exhibited the petal effect.

Ferrofluid-molding method for polymeric microlens arrays fabrication

This study proposes a method named as ferrofluid-molding method for polymer microlens array fabrication. In this method, the master of the mother mold for microlens molding is an array of ferrofluid droplets. We generated droplet arrays by inducing the droplet’s magnetic hydrodynamic instability under different magnetic fields, and used the field-dependent droplet dimensions to fabricate numerous mold cavities. By this we could fabricate arrays of microlens with different bottom area, height, radius of curvature, and focal length. From our analysis, all the fabricated microlens arrays possessed good uniformity, and the largest numerical aperture of our microlens array was found as 0.54. In addition, we also designed a light uniformity experiment to demonstrate a potential application of our microlens arrays.

To Fabricate Bragg Grating on D-Shaped Optical Fibre by Micro-Pressing Method

In this paper, we proposed a method to fabricate a D-shaped optical fiber of Bragg surface grating filter component by D-shaped fiber polishing along with photolithography、holographic interference lithography technologies and micro-molding process. The optical fiber was side-polished until it reaches the core of fiber. The master Bragg grating was first fabricated on the positive photoresister by using the holography interference lithography, then the patterned resist was used as a mother mold to transfer the pattern onto a hard polydimethylsiloxane (hPDMS)/ polydimethylsiloxane (PDMS) mold. The gratings pattern on hPDMS/PDMS was then transferred onto the UV polymer on the surface of a D-shaped fiber using a UV replication process. The transmission spectra of the resulting gratings were measured, with test results showing the transmission dip of -17dB , and 3-dB-transmission bandwidth of 9nm.

Fluorocarbon film-assisted fabrication of a CoNi mold with high aspect ratio for nanoimprint lithography

The availability of durable molds with nanometer-scale features is a bottleneck for nanoimprint lithography and nano-injection molding. Silicon (Si) nanomolds are typically fabricated by electron beam lithography, which is a very expensive technology, and furthermore, the lifetime of the Si mold is also short. This paper presents a very cost effective method for the fabrication of wafer level CoNi nanomolds with an improved residual stress profile without the consumption of a silicon mother mold. For this purpose, a 20nm fluorocarbon antistiction film was applied to the silicon mold prior to seed layer deposition and electroplating to ease the separation of the metal mold without sacrificing a costly mother mold. Step coverage of the fluorocarbon film was found to be dependent on the aspect ratio of nanoscale features. The degree and nature of the stress, as well as the cobalt content in the electroformed mold, were controlled by changing the anode-to-cathode gap. A 6-inch CoNi nanomold was successfully duplicated without consuming the mother mold with this method.

Perfusable multi-scale channels fabricated by integration of nanoimprint lighography (NIL) and UV lithography (UVL)

Numerous microfluidic devices have been applied to bioassays. Decreasing amount of liquid solutions helps to reduce sample waste and reagent consumption. Increasing sensitivity with fast reactions is another advantage. However, further downsizing of microfluidic devices brings difficulties in perfusing solutions due to a pressure drop, which is essential in bioassays. Here, we report a perfusable channel array in submicrometer to micrometer scale fabricated by integrating nanoimprint lithography (NIL) and UV lithography (UVL). Two lithography techniques are used to fabricate multiscale SU-8 mother mold for poly(dimethylsiloxane) (PDMS) replicas. SU-8 is an appropriate material as a mold due to mechanical stability and chemical resistance. However, it causes problems in a NIL process such as SU-8 residue on a silicon mold after demolding from a patterned SU-8 surface. To keep the compatibility of SU-8 in NIL process, UV-assisted NIL is employed to fabricate the line-and-space pattern for the channel array and microscale structures for microchannels were defined by UVL. NIL provides high throughput and high resolution patterns for the channel array, while UVL defines micrometer scale channels as interface between a user and the channel array. The fabricated device consists of a channel array (w=0.5-2@mm, h=1-2@mm, l=200@mm) and 2@mm scale channels (w=250@mm, h=50@mm, l=5mm). These micrometer scale channels are used for inlet or outlet of the channel array to deliver solutions. We demonstrated exchanging solutions using fluorescent solutions. Repetitive increase and decrease of fluorescent intensity proved the solution exchange in channel array.

Fabrication of Large-Area CoNi Mold for Nanoimprint Lithography

A cobalt–nickel (CoNi) alloy stamp of 140 mm diameter and 300 µm thickness was fabricated for nanoimprint lithography (NIL) from a Si mother mold with nanofeatures by using a stress-free electroforming method. CoNi alloys were electrodeposited in a chloride bath, and the effect of the flow velocity of a plating solution on CoNi film stress was investigated. The compositions of CoNi alloy films were investigated by changing the flow rate and bath concentration of CoCl2. The stress of the CoNi deposit was reduced to almost zero in an electrolyte containing 0.008 M CoCl2 in the flow rate range of 1–2 m/s. The multiple duplication of a stress-free CoNi alloy stamp was carried out without the use of a costly Si mother mold. Duplicated patterns on the CoNi alloy stamp were compared with those of the Si mother mold by field emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM).

Fabrication of Large-Area CoNi Mold for Nanoimprint Lithography

A cobalt–nickel (CoNi) alloy stamp of 140 mm diameter and 300 µm thickness was fabricated for nanoimprint lithography (NIL) from a Si mother mold with nanofeatures by using a stress-free electroforming method. CoNi alloys were electrodeposited in a chloride bath, and the effect of the flow velocity of a plating solution on CoNi film stress was investigated. The compositions of CoNi alloy films were investigated by changing the flow rate and bath concentration of CoCl2. The stress of the CoNi deposit was reduced to almost zero in an electrolyte containing 0.008 M CoCl2 in the flow rate range of 1–2 m/s. The multiple duplication of a stress-free CoNi alloy stamp was carried out without the use of a costly Si mother mold. Duplicated patterns on the CoNi alloy stamp were compared with those of the Si mother mold by field emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM).

Using Micro-Pressing Method to Fabricate Bragg Grating on D-Shaped Optical Fiber

In this paper, we proposed a method to fabricate a D-shaped optical fiber of Bragg surface grating filter component by D-shaped fiber polishing along with photolithography、holographic interference lithography technologies and micro-molding process. The optical fiber was side-polished until it reaches the core of fiber. The master Bragg grating was first fabricated on the positive photoresister by using the holography interference lithography, then the patterned resist was used as a mother mold to transfer the pattern onto a hard polydimethylsiloxane (hPDMS)/ polydimethylsiloxane (PDMS) mold. The gratings pattern on hPDMS/PDMS was then transferred onto the UV polymer on the surface of a D-shaped fiber using a UV replication process. The transmission spectra of the resulting gratings were measured, with test results showing the transmission dip of -17dB , and 3-dB-transmission bandwidth of 9nm.

Development of Large Area CoNi Alloy Electrodeposition Process for Stress Free Electroforming Mold

A 140mm CoNi alloy stamp for NIL was fabricated from a nano Si mother mold by using stress free electroforming method. CoNi alloys were electrodeposited from cobalt-nickel chloride electrolyte to investigate the influence of flow velocity of plating solution on CoNi film stress. Co and Ni contents were able to be controlled by changing flow rates and bath concentration of CoCl2. The stress was reduced to 0 in the solution containing 0.008M CoCl2 at the flow velocity of 1 to 2 m/s. The process allows deposition of stress free CoNi alloys. The multiple duplication of a CoNi alloy stamp is possible without the consumption of costly Si mother stamp. Duplicated patterns on CoNi alloy stamp were compared with those of Si mother mold by using field emission scanning electron microscopy (FE-SEM) and atomic force microscophy (AFM).

Reinforcement of a poly(dimethyl siloxane) mold with high aspect ratio microstructures via a gas–liquid phase sol–gel process

A gas–liquid phase sol–gel process was proposed to reinforce a poly(dimethyl siloxane) (PDMS) mold with high aspect ratio microstructures (HARMs) for micromolding. Unlike the conventional sol–gel process or in situ precipitation of silicate nanoparticles (SiO2) inside the PDMS network, the vapor of water and aminomethyl propanol-95 permeated through the PDMS which was pre-soaked with tetraethoxy silane (TEOS), leading to the occurrence of hydrolysis and condensation and reinforcement of the PDMS. The reinforced PDMS mold with HARMs was used for micromolding, and high replication accuracy was achieved. The proposed technique not only prevents the surface of microstructures on the mold from potential agglomeration of particles but also allows for the repetitive usage of the silicon mother mold without damage.

Laser Molding in Polymeric Materials Using Femto-Second Laser Pulse and Replication via Electroforming

The upheaval structure on the surface of polymer induced by the irradiation of a near-infrared (NIR) femto-second laser pulse in polymer bulk was investigated. Copolymers, such as poly(acrylonitrile-styrene) (AS) and poly(acrylonitrilebutadiene-styrene-methyl methacrylate) (ABSM) produced upheaval structures with a flattop just like the crater of a volcano, whereas homopolymers with relatively high glass transition temperature (Tg), such as polycarbonate (PC) and polyether imide (PEI) were more often formed a bell-shaped upheaval structure. A micro-lens effect was observed for the bell-shaped upheaval structure, but that effect was not observed in the case of copolymers with a flattop structure. Replication of the bell-shaped upheaval structure in PC was carried out by electroforming (non-electrolytic plating of Ni and the following electrolytic plating of Ni) and potting approximately 30 wt% THF solution of AS copolymer. A micro-scale bell-shaped upheaval structure in PC induced by a laser pulse was replicated using a Ni mother mold with suitable precision, and the replicated bell-shaped structure also showed a micro-lens effect.