Laser-induced Chemical Liquid Phase Deposition Research Articles

The Correlation between the Structures of Bimetallic Tartrate Complexes in Solutions for Laser-induced Synthesis and Sensor Characteristics of Microbiosensors Materials

Background: Determination of diagnostically significant components of biological ma-terials using enzyme-free microscopic sensors is an urgent scientific task, which is being worked on by a significant number of scientific groups in the world. This is due to the fact that microscop-ic sensor-active tracks on inert surfaces can be obtained without preliminary manufacturing of precision templates. Methods: Laser Induced Chemical Liquid Phase Deposition (LCLD) is a laser technology that al-lows the deposition of microsized conductive tracks from aqueous solutions of transition metal compounds at the focus of a laser beam. These tracks can be formed by one or two metals at the same time. The possibility of obtaining complexes in solution in which two different metals inter-act with one common coordination sphere of the ligand is of particular interest. The structure of such complexes is still insufficiently studied. Results: The present study supplements the missing information on tartaric acid complexes, which can simultaneously coordinate two metals, for example, copper, nickel, silver, iron, and cobalt. Heterophase LCLD demonstrates high sensory activity in the electrochemical oxidation/reduction of glucose and hydrogen peroxide. Bimetallic deposits can be obtained in two ways. The first method consists of successive precipitation from a solution containing an ion of one metal, then another on top of the first. The second way is to create a solution in which two metals and one lig-and are simultaneously present. Laser deposition is carried out in one stage. In practice, the possi-bility of the second method is not always realized. Conclusion: In the present work, the basic principles of the formation of heterophase bimetallic sensor-sensitive porous material with a highly developed surface under the action of laser radia-tion have been analyzed, and new reference data have been accumulated on the structure of tar-trate complexes containing two metals.

Formation of calcium-phosphate-based coatings on titanium by laser-induced deposition in liquid environment

Herein, a laser-induced chemical liquid-phase deposition (LCLD) technology was developed to synthesize a calcium phosphate (CaP)-based coating on Ti. Petal-like deposits were formed directly on the recast layer of Ti in a solution containing Ca and P under laser irradiation. The recast layer, containing elements in the deposit and Ti, acted as an interfacial layer between the coating and substrate. An increase in the laser power density increased the uniformity and size of the deposits. Zn ions can be incorporated into CaP deposits during LCLD, providing antibacterial activity against Escherichia coli and improving the corrosion resistance of Ti. Both CaP and Zn-doped CaP coatings exhibited good bioactivity owing to the high surface area of the petal-like deposits.

One-Stage Femtosecond Laser-Assisted Deposition of Gold Micropatterns on Dielectric Substrate.

In this study, a simple one-stage laser-assisted metallization technique based on laser-induced backside wet etching and laser-induced chemical liquid-phase deposition is proposed. It allows for the fabrication of gold micropatterns inside the laser-written trace on a glass substrate. The reduction and deposition of gold inside and outside the laser-ablated channel were confirmed. The presence of Au nanoparticles on the surface of the laser-written micropattern is revealed by atomic force microscopy. The specific resistivity of the gold trace formed by ultrafast light-assisted metal micropatterning on a dielectric glass substrate is estimated as 0.04 ± 0.02 mΩ·cm. The obtained results empower the method of the selective laser-assisted deposition of metals on dielectrics and are of interest for the development of microelectronic components and catalysts, heaters, and sensors for lab-on-a-chip devices.

Laser-Induced Chemical Liquid-Phase Deposition Plasmonic Gold Nanoparticles on Porous TiO2 Film with Great Photoelectrochemical Performance

This paper considers the photoelectrochemical characteristics of a composite porous TiO2 thin film with deposited plasmonic gold nanoparticles. The deposition of gold nanoparticles was carried out by the laser-induced chemical liquid-phase deposition (LCLD) method. The structural characteristics of the composite have been studied; it has been shown that the porous TiO2 film has a lattice related to the tetragonal system and is in the anatase phase. Gold nanoparticles form on the surface of a porous TiO2 film. A complex of photoelectrochemical measurements was carried out. It was shown that the deposition of plasmonic gold nanoparticles led to a significant increase in the photocurrent density by ~820%. The proposed concept is aimed at testing the method of forming a uniform layer of plasmonic gold nanoparticles on a porous TiO2 film, studying their photocatalytic properties for further scaling, and obtaining large area Au/TiO2/FTO photoelectrodes, including in the roll-to-roll process.

Fast Fabrication of Conductive Copper Structure on Glass Material Using Laser-Induced Chemical Liquid Phase Deposition

Glass is a very stable material at room temperature and has good resistance to gas, bacteria, and organisms. Due to the development of the electronic industry, the industrial demand for creating a conductive pattern on glass is increasing rapidly. To create conductive circuit patterns on the glass surface, non-contact methods based on high energy sources or chemical methods are generally used. However, these methods have disadvantages such as low conductivity, high cost, and size limitations. Processes such as LCLD (laser-induced chemical liquid phase deposition) have been widely studied to solve this problem. However, it has a fatal disadvantage of being slow. Therefore, in this study, various process changes were attempted to improve productivity and conductivity. In particular, sufficient thermal energy was supplied with high laser power for a stable chemical reduction, and the scanning path was changed in various shapes to minimize the ablation that occurs at this time. Through this, it was possible to disperse the overlapped laser energy of high power to widen the activation area of the reduction reaction. With this proposed LCLD process, it is possible to achieve good productivity and fabricate conductive circuit patterns faster than in previous studies.

Deposition of Durable Micro Copper Patterns into Glass by Combining Laser-Induced Backside Wet Etching and Laser-Induced Chemical Liquid Phase Deposition Methods.

Glass is a well-known non-conductive material that has many useful properties, and considerable research has been conducted into making circuits on glass. Many deposition techniques have been studied, and laser-induced chemical liquid phase deposition (LCLD) is a well-known and cost-effective method for rapid prototyping of copper deposition on glass. However, the deposition results from the LCLD method on the surface of glass, which shows an issue in its detachment from the substrates because of the relatively low adhesion between deposited copper and the nontreated glass surface. This problem undermines the usability of deposited glass in industrial applications. In this study, the laser-induced backside wet etching (LIBWE) method was performed as a preceding process to fabricate microchannels, which were filled with copper by LCLD. Additional durable copper wire was produced as a result of the enhanced adhesion between the glass and the deposited copper. The adhesion was enhanced by a rough surface and metal layer, which are characteristics of LIBWE machining. Furthermore, the proposed method is expected to broaden the use of deposited glass in industrial applications, such as in stacked or covered multilayer structures with built-in copper wires, because the inserted copper can be physically protected by the microstructures.

Laser-induced deposition of nanostructured copper microwires on surfaces of composite materials

Microelectronics industry is growing fast and the rate of new devices' development increases every year. Therefore, methods for simple and high-precision metal coating on dielectrics are needed. Existing methods do not allow performing the high-precision metal deposition without using photomasks, while making a photomask for each prototype is a long and expensive process. One of the methods of maskless metal deposition is laser-induced chemical liquid-phase deposition (LCLD). In this work we show the effect of substrate surface type on a result of LCLD. Deposited copper structures were characterized by SEM, EDX and impedance spectroscopy. The results show that laser-induced copper deposition is highly affected by the surface being a homogeneous or composite material. It was found that the deposits with low resistivity and high quality metal localization mostly appear on the two-phase surfaces. In contrast, deposits on one-phase surfaces exhibited poor topology of copper material. Statistical modeling was involved to describe this phenomenon.

Laser-induced synthesis of metallic silver-gold nanoparticles encapsulated in carbon nanospheres for surface-enhanced Raman spectroscopy and toxins detection

Metallic silver-gold nanoparticles (1–5 nm) encapsulated into carbon nanospheres (20–30 nm) were synthesized via laser-induced chemical liquid phase deposition. The obtained carbon-silver-gold nanostructures were characterized by high specific surface area and demonstrated high sensitivity as a material for surface-enhanced Raman scattering and adsorption properties allowing analyte extraction from a dilute solution for quantitative monitoring of low concentration components.

The influence of non-ionic surfactants on laser-induced copper deposition

We describe the laser-induced chemical liquid phase deposition of copper using a solution containing a non-ionic surfactant on substrates comprising either an oxide glass or a glass-ceramic Sitall. Our results demonstrate that the addition of the surfactant to the deposition solution results in improved structural topology in the deposited copper layer. Our data confirm that the use of a non-ionic surfactant can reduce the negative influence of gas formation during the deposition process.

Laser-induced chemical liquid-phase deposition of copper on transparent substrates

Laser-induced chemical liquid phase deposition allows maskless manufacturing of metallic structures on the surface of dielectrics and is prospected to be a promising tool in the field of microelectronics and microfluidics. The aim of the work presented here is to combine this deposition method with a related micro-structuring method known as laser-induced backside wet etching. Fabricating both, microstructured surface structures and subsequent deposition of conducting patterns within the same setup would be an interesting tool for rapid prototyping.To demonstrate the functional principle of this combined approach conductive copper lines were deposited at the backside of both polished and structured soda lime glass substrates by using a focused, scanning ns-pulsed Ytterbium fiber laser at 532nm wavelength. The deposition process is initiated by a photo induced reaction of a CuSO4-based liquid precursor in contact with the backside of the substrate. The obtained metallic copper deposits are crystalline, stable under ambient conditions and have a conductivity in the same order of magnitude as bulk copper.

Laser-induced chemical liquid phase deposition of copper from aqueous solutions without reducing agents

Laser-induced chemical liquid phase deposition of copper without a traditional reducing agent has been used for the first time to obtain conductive patterns on a dielectric surface having a reducing ability. It is shown that phenol-formaldehyde binder of the dielectric (glass fibre) can successfully play the role of a reducing agent in this process. The resulting copper sediments have low electrical resistance and good topology.

Side reactions during laser-induced deposition of copper from aqueous solutions of CuII complexes

The composition of the gas phase formed during laser-induced chemical liquid phase deposition (LCLD) of copper was studied. Based on the results of a mass spectrometric study of the gases, 1H NMR spectra of the autocatalytic solutions, EDX spectra of the copper deposit, and the dielectric substrate, side reactions of organic components of the solutions at the laser beam focusing point were suggested.

Laser-induced heterometallic phase deposition from solutions of supramolecular complexes

Heterometallic (Au–Cu) phase precipitation on the surface of soda-lime glass as a result of laser-induced chemical liquid phase deposition (LCLD) is demonstrated for the first time. The precipitation of heterometallic structures was carried out under Ar+ laser irradiation from the solutions of supramolecular complexes. Energy dispersive X-ray (EDX) analysis showed that the deposits consist of both Au and Cu. Morphology of the deposited structures was found to be dependent on the used solvents: delocalized sparse surface structures in the case of the dichloromethane solution, close packed nanoparticles for the dimethyl formamide and homogeneous phase with nano-pores for the acetone solution. In accordance to the SEM photos and scan EDX analysis the homogeneous heterometallic phase with fixed Au/Cu ratio was achieved for the acetone solution of supramolecular complex. The observed formation of the heterometallic phase was explained by the laser-initiated intramolecular reduction process of the supramolecular metal core.

ChemInform Abstract: Laser‐Induced Chemical Liquid Phase Deposition of Metals: Chemical Reactions in Solution and Activation of Dielectric Surfaces

AbstractReview: 92 refs.

Optimization of the solution composition for laser-induced chemical liquid phase deposition of copper

Optimal compositions of autocatalytic solutions for laser-induced deposition of copper were established. The copper salt concentration range in which the process gives the best results was determined. It is shown that optical microscopy, as a means of controlling the topology of the deposited structures, has limited applicability. The results obtained by this method should be verified by alternative techniques, e.g., electron microscopy or measurements of the electrical conductivity of deposited structures.

Effect of salt precursor on laser-assisted copper deposition

Continuous copper structures were precipitated on microscope cover glasses by the laser-induced chemical liquid phase deposition (LCLD) method. The deposition of copper was realized from both CuSO4- and CuCl2-based electrolyte solutions. The surface morphology and the chemical composition of the deposits were analyzed with a scanning electron microscope and energy dispersive X-ray spectrometer (EDX). The dependence of the characteristics (width and resistance) of the copper deposits on the laser power, temperature and the salt precursor was examined. The observed strong influence of the solution temperature and the salt precursor on the deposits characteristics was explained by the specific chemical features of the Cu(II)→Cu(0) reduction process.

Laser-induced copper deposition on the surface of an oxide glass from an electrolyte solution

Continuous copper patterns were grown on the surface of oxide glass substrates through laserinduced chemical liquid-phase deposition (LCLD). The deposition was performed with the use of a continuouswave argon laser operating in a multimode regime. The deposition occurred as a result of the reducing chemical reaction initiated by laser radiation. Continuous metal patterns were produced by scanning focused laser radiation along the substrate-electrolyte interface. The morphology and the chemical composition of the deposited patterns were examined with the use of a CEM-SCAN 4 DV scanning electron microscope equipped with an energy-dispersive spectrometer. The morphology of the deposited patterns was investigated as a function of the laser radiation power and the number of scans. It was demonstrated that high-quality continuous patterns can be fabricated using one scan of the laser beam.

Laser-assisted via hole metallization in PCB materials

A novel via hole metallization method is presented, where the vias are drilled in polyimide/copper (PI/Cu) flexible printed circuit boards (PCBs) using KrF excimer pulses, and then pre-metallized using a scanned Ar+ laser. In the premetallization step, a thin (20–50 nm) and narrow (2–10 μm) palladium layer is deposited on the polyimide-covered side of the PCB and on the wall of the vias using the laser-induced chemical liquid-phase deposition method. After the pretreatment, the Pd covered holes are immersed into a Cu electroless plating bath. Plated copper vertical and horizontal interconnects are analyzed by optical microscopy, focused ion beam, profilometry and resistivity measurements. The results show that the copper deposits formed on the pre-metallized surface of PCBs have high chemical purity, excellent adhesion and almost bulk conductivity, but, so far, due to unclear reasons, high through hole resistance.

Laser-assisted metal deposition from liquid-phase precursors on polymers

In this work, a short review is presented for results utilizing the technique of laser-assisted metallization of dielectrics. Experimental efforts and results related to the metal (palladium (Pd), copper (Cu) and silver (Ag)) deposition on polymeric materials (polyimide (PI), mylar) are reported. These polymers and metals are chosen due to their growing importance in the rapidly-developing microelectronics packaging industry. The method of laser-induced chemical liquid-phase deposition (LCLD) offers many advantages compared to other techniques such as laser-induced forward transfer (LIFT), pulsed-laser deposition (PLD) and laser-assisted chemical vapor-phase deposition (LCVD). The LCLD is time and cost effective because vacuum tools and special pre-treatments are not required. The consumed chemicals used in precursors are non-harmful and easy to handle due to the liquid phase. For the optimal physical and chemical properties of deposits, the laser and solution parameters are varied. XeCl and KrF excimer and Ar + lasers are employed for executing the palladium, Ag and/or Cu formation on the polymer substrates. Chemical and physical analyses of the formed metal patterns are performed by EDX, XRD, FESEM, SEM, resistance and adhesion measurements.

Laser direct writing of palladium on polyimide surfaces from solution

Conductive palladium (Pd) patterns were generated by laser-induced chemical liquid-phase deposition (LCLD) on polyimide (PI) substrates using a continuous Ar + laser beam. The deposition process was executed from the amine complex solution of Pd 2+ ions. Dependence of the characteristics of the laser direct written patterns on scanning speed of the laser beam, number of scans and laser power was examined. Deposits were characterised by Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive Spectrometry (EDS), and profilometric measurements. The resistance of the patterns was also measured. It was found that good quality lines — narrow, homogeneous, and with high conductivity and adhesion — were achieved under optimized conditions.