A NOTE ON INORGANIC POLYMERS SEMICONDUCTOR MATERIALS

The extended crystallographic defects introduced into some oxide catalysts under operating conditions may be a consequence and accommodation of the changes produced by the catalytic activity, rather than always being the origin of the reactivity. Operation without such defects has been established for the commercially important tellurium molybdate system. in addition it is clear that the point defect density and the electronic structure can both have a significant influence on the chemical properties and hence on the effectiveness (activity and selectivity) of the material as a catalyst. SEM/probe techniques more commonly applied to semiconductor materials, have been investigated to supplement the information obtained from in-situ environmental cell HVEM, ultra-high resolution structure imaging and more conventional AEM and EPMA chemical microanalysis.

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Revisiting the passivation of stainless steels and other passive CRAs

Matériaux & Techniques ◽

10.1051/mattech/2018020 ◽

2018 ◽

Vol 106 (1) ◽

pp. 107 ◽

Cited By ~ 3

Author(s):

Jean- Louis Crolet

Keyword(s):

Electrical Conductivity ◽

Metal Ions ◽

Base Metal ◽

Stainless Steels ◽

Electronic Conductivity ◽

Transport Processes ◽

General Knowledge ◽

Inorganic Polymers ◽

Faraday Cage

All that was said so far about passivity and passivation was indeed based on electrochemical prejudgments, and all based on unverified postulates. However, due the authors’ fame and for lack of anything better, the great many contradictions were carefully ignored. However, when resuming from raw experimental facts and the present general knowledge, it now appears that passivation always begins by the precipitation of a metallic hydroxide gel. Therefore, all the protectiveness mechanisms already known for porous corrosion layers apply, so that this outstanding protectiveness is indeed governed by the chemistry of transport processes throughout the entrapped water. For Al type passivation, the base metal ions only have deep and complete electronic shells, which precludes any electronic conductivity. Then protectiveness can only arise from gel thickening and densification. For Fe type passivation, an incomplete shell of superficial 3d electrons allows an early metallic or semimetallic conductivity in the gel skeleton, at the onset of the very first perfectly ordered inorganic polymers (- MII-O-MIII-O-)n. Then all depends on the acquisition, maintenance or loss of a sufficient electrical conductivity in this Faraday cage. But for both types of passive layers, all the known features can be explained by the chemistry of transport processes, with neither exception nor contradiction.

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Chemical-Mechanical Planarization of Semiconductor Materials

10.1007/978-3-662-06234-0 ◽

2004 ◽

Cited By ~ 85

Keyword(s):

Chemical Mechanical Planarization ◽

Semiconductor Materials

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Deriving ultrapure three-dimensional semiconductor materials under space vacuum conditions

Kosmìčna nauka ì tehnologìâ ◽

10.15407/knit2003.05.030 ◽

2003 ◽

Vol 8 (5-6) ◽

pp. 30-32

Author(s):

B.E. Paton ◽

◽

E.A. Asnis ◽

S.P. Zabolotin ◽

P.I. Baranskii ◽

...

Keyword(s):

Three Dimensional ◽

Semiconductor Materials ◽

Space Vacuum

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Surface Modification of Poly (alkyl/Arylphosphazene) Thin Films

MRS Proceedings ◽

10.1557/proc-629-ff9.5 ◽

2000 ◽

Vol 629 ◽

Author(s):

John V. St. John ◽

Patty Wisian-Neilson

Keyword(s):

Thin Films ◽

Surface Modification ◽

Chemical Resistance ◽

Chemical Properties ◽

Inorganic Polymers ◽

Thin Polymer Films ◽

Hydrophilic Interactions ◽

Carboxylic Acid Groups ◽

Polymer Interface ◽

Thin Polymer

ABSTRACTPoly (methylphenylphosphazene) (PMPP) is an example of a unique class of inorganic polymers with alternating – (P=N)– backbones. Chemical modification of bulk PMPP can result in changes of physical properties such as chemical resistance, onset temperature of thermal degradation, elasticity, and flexibility. Surface modification of PMPP allows tailoring of the chemical properties at the polymer interface while maintaining the integrity of the bulk polymer. In this research, PMPP thin films were treated to form carboxylate or carboxylic acid groups at the surface. Surface modification was monitored by following changes in contact angle. The hydrophobic/hydrophilic interactions of carboxylated PMPP surfaces allow for mesoscale interactions of thin polymer films.

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