Adhesion of Ni-structures on Al 2 O 3 ceramic substrates used for the sacrificial layer technique

Kunz, Th.; Mohr, J.; Ruzzu, A.; Skrobanek, K.D.; Wallrabe, U.

doi:10.1007/s005420050179

Cited by 11 publications

(5 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among this class are reports, for example, about Pt-nanoclusters on TiO 2 surfaces [165], specific ZSM-5 zeolite layers [166], and catalysts for reforming processes [167]. …”

Section: Taylor-made Catalystsmentioning

confidence: 99%

Microchemical Engineering: Components, Plant Concepts, User Acceptance – Part II

Hessel

Löwe

2003

Chem Eng & Technol

View full text Add to dashboard Cite

Over the last five years, many activities have focused on the unexploited field of carrying out reactions on small scales. Due to the rapid development of new components, this paper deals with recent developments only in a compressed form. An important point is the analysis of possible plant concepts for microreactors and whether these are a sensible option. Due to the enormous difference in size between the microchannels and the fluid periphery of possible components this is not just a technical question. It touches on the microtechnology concept as a whole. The direction in which the field should be developed and which measures can be taken to influence its development are questions that are addressed here with respect to the big industrial interest in microreactors. Reactors for Photochemical and Electrochemical ProcessingMicroreactors may possibly be capable of reevaluating processes which so far have been poorly developed both in the lab and in the chemical industry. Among such processs certainly are electrochemical reactions and particularly photochemical reactions. Photochemical and Electrochemical ProcessesIn view of the low quantum yield of photochemical processes even for respective lab-scale equipment, it would appear that guiding of thin fluid layers in transparent microreactors, e.g. mixer-reactors, in close proximity to a radiation source should be beneficial. At the Massachusetts Institute of Technology (MIT), Cambridge (USA), researchers carried out the pinacol synthesis using benzophenone as reactant in a pyrex/silicon microreactor equipped with a miniature UV lamp (k = 366 nm) (see Fig. 20) [98,99].An electrochemical microreactor was developed at IMM which combines the advantages of thin-layer cell technology (namely, current efficiencies up to 100 %, absence of conducting salt) and microchemical processing (e.g., isothermal processing, good mass transfer). The electrochemical microreactor has a parallel-plate architecture. Using this device, an increase in selectivity for the synthesis of anisaldehyde from 4-methoxytoluene was detected [100]. Heat Transfer Fast Heating up for Chlorination of AlkanesThe chlorination of alkanes [102] performed by the Axiva company serves as a good and successful example based on the motto ªas much miniaturization as necessary, not as possibleº. The tube reactors used till now needed too much time to reach a certain temperature level or even exhibited temperature maxima above the target value, in effect similarly detrimental as a hot spot. To improve these features, IMM developed monolithic heating modules that are externally heated. The . UV absorption of reaction mixtures resulting from pinacol reaction using benzophenone in isopropanol at various flow rates and residence times, respectively. A comparison of these results to HPLC measurements at the same mixtures reveals that these UV in-line spectra are accurate and hence can be used to monitor the course of reaction. Source: K. Jensen, MIT, Department of Chemical Engineering, Cambridge (USA)

show abstract

“…Among this class are reports, for example, about Pt-nanoclusters on TiO 2 surfaces [165], specific ZSM-5 zeolite layers [166], and catalysts for reforming processes [167]. …”

Section: Taylor-made Catalystsmentioning

confidence: 99%

Microchemical Engineering: Components, Plant Concepts, User Acceptance – Part II

Hessel

Löwe

2003

Chem Eng & Technol

View full text Add to dashboard Cite

show abstract

“…While PMMA adhesion has been reasonably well studied, only a few studies have addressed the equally important issue of adhesion between the substrate and electrodeposited metal. Kunz et al examined the adhesion of nickel to ceramic wafers metallized with layers of chrome and gold [24]. They demonstrated that adsorbed water on the ceramic surface and the temperatures used for depositing the metal films played important roles in metal adhesion.…”

Section: Past Researchmentioning

confidence: 99%

Resist substrate studies for LIGA microfabrication with application to a new anodized aluminum substrate

Griffiths¹,

Losey²,

Hachman³

et al. 2005

J. Micromech. Microeng.

View full text Add to dashboard Cite

Resist substrates used in the LIGA process must provide high initial bond strength between the substrate and resist, little degradation of the bond strength during x-ray exposure, acceptable undercut rates during development and a surface enabling good electrodeposition of metals. Additionally, they should produce little fluorescence radiation and give small secondary doses in bright regions of the resist at the substrate interface. To develop a new substrate satisfying all these requirements, we have investigated secondary resist doses due to electrons and fluorescence, resist adhesion before exposure, loss of fine features during extended development and the nucleation and adhesion of electrodeposits for various substrate materials. The result of these studies is a new anodized aluminum substrate and accompanying methods for resist bonding and electrodeposition. We demonstrate the successful use of this substrate through all process steps and establish its capabilities via the fabrication of isolated resist features down to 6 µm, feature aspect ratios up to 280 and electroformed nickel structures at heights of 190 to 1400 µm. The minimum mask absorber thickness required for this new substrate ranges from 7 to 15 µm depending on the resist thickness.

show abstract

“…The optical benches, the static motor parts, and the mirror stops are fabricated simultaneously using LIGA technology. Because of the electromechanical function of the motors, the struc-162 tures are made from electroplated nickel on a sacrificial layer [31]. The rotors with the attached double mirrors are manufactured similarly on a separate substrate and are set manually above the stators.…”

Section: Optical Cross Connect With Rotating Mirrors Actuated By Elecmentioning

confidence: 99%

Modular Microoptical Systems for Sensors and Telecommunication

Wallrabe

Mohr

2003

Sensors Update

Self Cite

View full text Add to dashboard Cite

This paper focuses on fabrication and assembly processes of modular and hybrid microoptical systems in use in sensor and telecommunication fields. These microoptical systems are made by a huge variety of processes, which are commonly known as microsystem technology. Nevertheless, quite a lot of them are based on the LIGA process, since LIGA is an "assembly friendly" technology.Modular microoptical systems typically comprise several functions incorporating mechanical or electromechanical components beside the optical elements. The assembly of the diverse submounts and components is performed actively as well as passively. In many cases, all of these functions can be combined on one single chip. In several cases, however, a pair of chips, which is assembled in a flip-chip like way, is used.The framework of the paper leads to a definition of the terminus "modular microoptical system" and argues for the advantages of such a modular design approach. It closes with some remarks on automatic assembly strategies.

show abstract

Adhesion of Ni-structures on Al 2 O 3 ceramic substrates used for the sacrificial layer technique

Cited by 11 publications

References 5 publications

Microchemical Engineering: Components, Plant Concepts, User Acceptance – Part II

Microchemical Engineering: Components, Plant Concepts, User Acceptance – Part II

Resist substrate studies for LIGA microfabrication with application to a new anodized aluminum substrate

Modular Microoptical Systems for Sensors and Telecommunication

Contact Info

Product

Resources

About