CVD mullite and mullite-alumina corrosion protection coatings for silicon based ceramics

Organic coatings are widely employed in the corrosion protection of most metal surfaces, particularly steel. They provide a barrier against corrosive species present in the environment, due to their high resistance to oxygen, water and ions transport. This study focuses on the evaluation of corrosion protection performance of epoxy paint on the carbon steel surface in chloride environment (3% NaCl) by Electrochemical Impedance Spectroscopy (EIS). The electrochemical behavior of painted surface was estimated by EIS parameters that contained paint film resistance, paint film capacitance and double layer capacitance. On the basis of calculation using EIS spectrums it was observed that pore resistance (Rpore) decreased with the appearance of doubled layer capacitance (Cdl) due to the electrolyte penetration through the film. This was further confirmed by the decrease of diffusion resistance (Rd) which was also the indicator of the deterioration of paint film protectiveness. Microscopic analyses have shown that oxidation dominates the corroded surfaces.

Download Full-text

Corrosion protection and control using nanomaterials

10.1533/9780857095800 ◽

2012 ◽

Cited By ~ 13

Author(s):

Viswanathan S. Saji ◽

Ronald Cook

Keyword(s):

Corrosion Protection ◽

Protection And Control ◽

And Control

Download Full-text

Charge Trapping and Degradation Properties of PZT Thin Films for MEMS

MRS Proceedings ◽

10.1557/proc-444-161 ◽

1996 ◽

Vol 444 ◽

Cited By ~ 1

Author(s):

Hyeon-Seag Kim ◽

D. L. Polla ◽

S. A. Campbell

Keyword(s):

Thin Films ◽

Loss Factor ◽

High Field ◽

Microelectromechanical Systems ◽

Charge Trapping ◽

Metal Organic ◽

Electrical Reliability ◽

Silicon Based ◽

Degradation Properties ◽

Organic Decomposition

AbstractThe electrical reliability properties of PZT (54/46) thin films have been measured for the purpose of integrating this material with silicon-based microelectromechanical systems. Ferroelectric thin films of PZT were prepared by metal organic decomposition. The charge trapping and degradation properties of these thin films were studied through device characteristics such as hysteresis loop, leakage current, fatigue, dielectric constant, capacitancevoltage, and loss factor measurements. Several unique experimental results have been found. Different degradation processes were verified through fatigue (bipolar stress), low and high charge injection (unipolar stress), and high field stressing (unipolar stress).

Download Full-text

Photoconductivity in Vacuum Deposited Films of Silicon-Based Polymers

MRS Proceedings ◽

10.1557/proc-444-191 ◽

1996 ◽

Vol 444 ◽

Author(s):

H. Okumoto ◽

M. Shimomura ◽

N. Minami ◽

Y. Tanabe

Keyword(s):

Charge Transfer ◽

Chemical Modification ◽

Electronic Transport ◽

Hole Transport ◽

Electron Acceptors ◽

Oxygen Atmosphere ◽

Dangling Bonds ◽

Silicon Based ◽

Deposited Films

AbstractSilicon-based polymers with σconjugated electrons have specific properties; photoreactivity for microlithography and photoconductivity for hole transport materials. To explore the possibility of combining these two properties to develop photoresists with electronic transport capability, photoconductivity of polysilanes is investigated in connection with their photoinduced chemical modification. Increase in photocurrent is observed accompanying photoreaction of poly(dimethylsilane) vacuum deposited films. This increase is found to be greatly enhanced in oxygen atmosphere. Such changes of photocurrent can be explained by charge transfer to electron acceptors from Si dangling bonds postulated to be formed during photoreaction.

Download Full-text

Use of Transparent Conductive Oxide Materials with Low Indices of Refraction in Amorphous Silicon-Based Solar Cell Technology

MRS Proceedings ◽

10.1557/proc-862-a21.1 ◽

2005 ◽

Vol 862 ◽

Author(s):

Scott J. Jones ◽

Joachim Doehler ◽

Tongyu Liu ◽

David Tsu ◽

Jeff Steele ◽

...

Keyword(s):

Solar Cell ◽

Amorphous Silicon ◽

Transparent Conductive Oxide ◽

Open Circuit ◽

Long Term Stability ◽

Back Reflectors ◽

Stability Issues ◽

Silicon Based ◽

Solar Cell Technology

AbstractNew types of transparent conductive oxides with low indices of refraction have been developed for use in optical stacks for the amorphous silicon (a-Si) solar cell and other thin film applications. The alloys are ZnO based with Si and MgF added to reduce the index of the materials through the creation of SiO2 or MgF2, with n=1.3-1.4, or the addition of voids in the materials. Alloys with 12-14% Si or Mg have indices of refraction at λ=800nm between 1.6 and 1.7. These materials are presently being used in optical stacks to enhance light scattering by Al/multi-layer/ZnO back reflectors in a-Si based solar cells to increase light absorption in the semiconductor layers and increase open circuit currents and boost device efficiencies. In contrast to Ag/ZnO back reflectors which have long term stability issues due to electromigration of Ag, these Al based back reflectors should be stable and usable in manufactured PV products. In this manuscript, structural properties for the materials will be reported as well as the performance of solar cell devices made using these new types of materials.

Download Full-text