Morphology and structure of composite catalysts of nickel on metal-ceramic substrate

L. L. Kuznetsova; V. I. Zaikovskii; A. V. Ziborov; L. M. Plyasova

doi:10.1007/bf02064727

Fabrication of ceramic substrate‐reinforced and free forms by mandrel plasma spraying metal–ceramic composites

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.572856 ◽

1985 ◽

Vol 3 (6) ◽

pp. 2450-2455 ◽

Cited By ~ 1

Author(s):

R. J. Quentmeyer ◽

G. McDonald ◽

R. C. Hendricks

Keyword(s):

Plasma Spraying ◽

Ceramic Composites ◽

Ceramic Substrate ◽

Metal Ceramic

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Studies of composite catalysts of nickel on metal-ceramic substrates

Reaction Kinetics and Catalysis Letters ◽

10.1007/bf02064726 ◽

1991 ◽

Vol 43 (2) ◽

pp. 545-552 ◽

Cited By ~ 5

Author(s):

L. L. Kuznetsova ◽

V. N. Ananin ◽

A. V. Pashis ◽

V. V. Belyaev

Keyword(s):

Ceramic Substrates ◽

Composite Catalysts ◽

Metal Ceramic

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Investigation of the Direct Plating Copper (DPC) on Al2O3, BeO or AlN Ceramic Substrates for High Power Density Applications

International Symposium on Microelectronics ◽

10.4071/isom-2016-tp43 ◽

2016 ◽

Vol 2016 (1) ◽

pp. 000079-000086 ◽

Cited By ~ 1

Author(s):

Ho-Chieh (Jay) Yu ◽

Jason Huang

Keyword(s):

Power Density ◽

High Power ◽

Substrate Material ◽

Ceramic Substrate ◽

High Power Density ◽

Power Module ◽

Ceramic Substrates ◽

Metal Ceramic ◽

Via Holes ◽

Pattern Resolution

Abstract In the high power module applications, the power increasing and the size shrinking becomes one of the major topics for the power module design. Due to both the power increasing and the size decreasing, the power density of the device will be much increased. Therefore, not only the thermal conductivity and stability of the substrate material but the long-term material reliability of the substrate have to be seriously considered. For these reasons, the ceramic PCB becomes one of the best solutions. The ceramic substrates now used are normally based on Ag-printed or direct bonding copper (DBC) technology. In the case of the Ag-printed ceramic substrate, the pattern resolution and metallization thickness are limited by the Ag-printed process. Also the combination strength of the silver and ceramic substrate by glass (which is normally mixed in the silver paste) is normally not good enough. A thermal dissipation barrier will then be formed between silver and ceramic substrate due to the poor thermal conductivity of the glass material. For the DBC ceramic substrate, DBC substrates are manufactured at 1065°C by the diffusion between ceramic and Cu/CuO layer. A thicker Cu layer thickness of normally more than 300 um is required in the thermal compressing bonding process. The Cu pattern resolution will then be limited by the thickness of the Cu layer. However, the about 5~10% of the voids exist randomly between ceramic and Cu layer is the other major issue. The resolution issues of the Ag-printed and DBC ceramic substrates make the limitation for the device density design (fine line/width and flip-chip device design become very difficult). The glass material in the Ag printed ceramic substrate and the 5~10% voids existence in DBC ceramic substrate may cause the reliability issue operating at a high power density applications. For high power density module applications, we introduce the DPC technology on the ceramic substrate. In DPC ceramic substrate system, the sputtered Ti is used as the combination material between Cu and ceramic substrate. And the first copper is then sputtered on the top of Ti layer as seed-layer for the following Cu electrode plating (second cupper layer). By the material and the sputtering process control, several ceramic substrate raw materials can be used, such as Al2O3, AlN, BeO, Si3N4 and so on. The Ti combined/buffer layer provides good adhesion strength and material stability. The second copper layer is plated by electrode casting plating to 3 to 5 oz. (100~150um) in thickness. The key technology of the metal trace plating is the material control of the sputter layers and the second copper layer stress release during plating. In the DPC system, the double layers design is available. The laser drilled via holes on the various ceramic substrates is introduced. The conducting of the front and back side is connected by the following plating process. The key technology of this process is the stability of the via-holes. We have to make sure the via-holes cleaning, impurity removing and material stability during high temperature laser drilled is well controlled. DPC ceramic substrates provide a better metal/ceramic interface uniformity and material reliability due to the stable Ti combination material and much less voids in the metal/ceramic interface. Also, the DPC ceramic substrates provide a gold pattern resolution of 50 um line space with tight tolerance of 20 um min. We believe the material characteristic make DPC a very suitable substrate material for high power module applications.

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The Direct plating copper (DPC) ceramic material on Al2O3/AlN or LTCC (Low-temperature co-fired ceramic) substrates

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/2016dpc-wp46 ◽

2016 ◽

Vol 2016 (DPC) ◽

pp. 001773-001790

Author(s):

Ho-Chieh (Jay) Yu ◽

Jason Huang

Keyword(s):

Electrical Resistance ◽

Ceramic Substrate ◽

Conducting Material ◽

Ceramic Substrates ◽

Direct Plating ◽

Key Technology ◽

Metal Trace ◽

Metal Ceramic ◽

Via Holes ◽

Multilayer Ceramic

RESEARCH BACKGROUND: The now used ceramic substrate or sub-mounted are normally based on Ag-printed, direct bonding copper (DBC) ceramic or LTCC (Low temperature co-fired ceramic)/HTCC (High temperature co-fired ceramic) technology.Due to the limit of the screen-printed process, the resolution and conducting material thickness the Ag-printed, LTCC and HTCC substrate are poor. The poor resolutions make these materials difficult to use in high density and flip-chip device design. And the related thinner conducting material (normally <20um) limits the power rating of the design.DBC is now widely applied in power circuit design, however, duo to the copper lamination process requirement, more than 300um in thickness of copper layer is needed. Any lower copper thickness design should have an extra costly grind to reach. Also, the DBC material is difficult to provide to the multilayer trace design. OUR GOAL: We want to provide a solution with multilayer ceramic substrate for high power and high device density applications. Besides, the material properties, the adhesion of the metal/ceramic also be considered. Following are the material characteristics required for the development:A low electrical resistance material: Copper.A thick trace material thickness of more than 3 oz.A high thermal conductivity and stability ceramics with via-holes for TSV plating (Drilled Al2O3/AlN substrate ) or non- shrinking LTCC materialHigh metal trace resolution whose line width and space could be only 50 umWell metal/ceramic adhesion uniformity and strength is required: The voids between metal/ceramic < 1%; The adhesion strength> 2 kg/2*2mm2. METHODS & RESULTS: Metal trace plating: For high resolution and lower material electrical resistance request of the trace metal, we introduce electrical casting direct-plating copper (DPC) technology. The first copper is sputtered on the ceramic substrate using Ti as combined/buffer layer between copper and ceramic to provide good adhesion strength and stability. The second copper is made by electrical casting process to increase its thickness to 3 to 5 oz. (100~150um). The key technology of the metal trace plating is the material control of the sputter layers and the second copper layer stress release during plating. Multilayer Ceramic substrates: For double layers design, we use sintered Al2O3 or AlN substrates with electrical conducting via-holes design. The via-holes are made by laser drilling. And the conducting of the front and back side is connected by the following plating process. The key technology of this process is the stability of the via-holes. We have to make sure the via-holes cleaning, impurity removing and material variation during high temperature laser drilled is well controlled. For the more than three layers design, the non-shrinking LTCC is used. The dimension mismatch of the non-shrinking LTCC can controlled less than 100um., much better than that of normal LTCC/HTCC. By the correction of the following DPC process, the tolerance of the metal trace can be controlled < 30 um. The key technology of this process is the non-shrinking LTCC technology and the adhesion of the DPC metal on LTCC material.

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Pd Nanoparticles Supported on TiO2 Nanotubes for Ethanol Oxidation in Alkaline Media

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.132.279 ◽

2010 ◽

Vol 132 ◽

pp. 279-286 ◽

Cited By ~ 2

Author(s):

Hou Hua Yang ◽

Yuan Hang Qin ◽

Sun Wen ◽

Xin Sheng Zhang ◽

Dong Fang Niu ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Tio2 Nanotubes ◽

Ethanol Oxidation ◽

Pd Nanoparticles ◽

Alkaline Media ◽

Composite Catalysts ◽

Morphology And Structure ◽

Oxidation Of Ethanol ◽

Scanning Electron

Pd electrocatalysts supported on TiO2 nanotubes (TNTs) were prepared and used for the oxidation of ethanol in alkaline media. The morphology and structure of the TNTs and the Pd-TNTs/Ti catalyst were characterized by field emission scanning electron microscopy (FESEM). The FESEM results showed that the nanotube structure could be obtained after Ti anodized for 40 min at 20 V under 25 °C, and the nanotube length increased with anodizing time. TNTs/Ti40, TNTs/Ti50 and TNTs/Ti90 templates were prepared with Ti anodized for 40 min, 50 min and 90 min respectively. The composite catalysts activities were measured by cyclic voltammetry (CV), impedance spectroscopy and chronoamperometry. The results indicated that the Pd-TNTs/Ti50 catalyst had higher catalytic activity for ethanol oxidation compared with Pd-TNTs/Ti40 and Pd-TNTs/Ti90 catalysts.

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Analytical and High-Resolution EM Study of Crystalline Phases formed at Metal-Ceramic Interface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135733 ◽

1990 ◽

Vol 48 (2) ◽

pp. 426-427

Author(s):

N. Merk ◽

A. P. Tomsia ◽

G. Thomas

Keyword(s):

Cross Section ◽

Dissimilar Materials ◽

Ceramic Materials ◽

Electron Micrograph ◽

Scanning Electron Micrograph ◽

Structural Applications ◽

Metal Ceramic ◽

The Subject ◽

Ceramic Compounds ◽

Scanning Electron

A recent development of new ceramic materials for structural applications involves the joining of ceramic compounds to metals. Due to the wetting problem, an interlayer material (brazing alloy) is generally used to achieve the bonding. The nature of the interfaces between such dissimilar materials is the subject of intensive studies and is of utmost importance to obtain a controlled microstructure at the discontinuities to satisfy the demanding properties for engineering applications . The brazing alloy is generally ductile and hence, does not readily fracture. It must also wett the ceramic with similar thermal expansion coefficient to avoid large stresses at joints. In the present work we study mullite-molybdenum composites using a brazing alloy for the weldment.A scanning electron micrograph from the cross section of the joining sequence studied here is presented in Fig. 1.

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