초록 ▼

A ceramic carrier and ceramic catalyst body used as NOxpurification catalysts for lean burn engines, which are inexpensive, exhibit high temperature durability and can maintain their catalytic function for extended periods. The ceramic carrier has a diffusion-inhibiting layer formed on the surface o

A ceramic carrier and ceramic catalyst body used as NOxpurification catalysts for lean burn engines, which are inexpensive, exhibit high temperature durability and can maintain their catalytic function for extended periods. The ceramic carrier has a diffusion-inhibiting layer formed on the surface of a cordierite honeycomb structure, to inhibit diffusion of alkali metals, alkaline earth metals, etc. carried as NOxstorage materials. The diffusion-inhibiting layer is composed of a ceramic material such as Y2O3,NiO or CeO2which does not react with alkali metals or alkaline earth metals at temperatures of up to 1000° C. and has a melting point of higher than 1000° C., and the diffusion-inhibiting layer inhibits diffusion of catalyst components such as potassium into the interior to prevent their reaction with cordierite, so that the durability is greatly enhanced without reducing catalytic performance.

대표청구항 ▼

A ceramic carrier and ceramic catalyst body used as NOxpurification catalysts for lean burn engines, which are inexpensive, exhibit high temperature durability and can maintain their catalytic function for extended periods. The ceramic carrier has a diffusion-inhibiting layer formed on the surface o

A ceramic carrier and ceramic catalyst body used as NOxpurification catalysts for lean burn engines, which are inexpensive, exhibit high temperature durability and can maintain their catalytic function for extended periods. The ceramic carrier has a diffusion-inhibiting layer formed on the surface of a cordierite honeycomb structure, to inhibit diffusion of alkali metals, alkaline earth metals, etc. carried as NOxstorage materials. The diffusion-inhibiting layer is composed of a ceramic material such as Y2O3,NiO or CeO2which does not react with alkali metals or alkaline earth metals at temperatures of up to 1000° C. and has a melting point of higher than 1000° C., and the diffusion-inhibiting layer inhibits diffusion of catalyst components such as potassium into the interior to prevent their reaction with cordierite, so that the durability is greatly enhanced without reducing catalytic performance. ping the first and second patterned photoresist layers; etching a portion of the UBM layer not under the second conductive structure; and reflowing the second conductive structure to form the bump structure. 12. The method of claim 11, wherein the second conductive structure is mushroom shaped. 13. The method of claim 11, wherein the first conductive structure is comprised of a material selected from the group consisting of copper and aluminum; the UBM layer is comprised of a material selected from the group consisting of Ti/Cu, Cr/Cu, Ti/Ni and Ni/Au; the second capping photoresist layer is negative liquid photoresist; and the second conductive structure is comprised of a alloy solder material selected from the group consisting of SnAg, PbSn, SnAgCu, SnBi and SnTn. 14. The method of claim 11, wherein the structure is a semiconductor structure. 15. The method of claim 11, wherein the structure includes an overlying passivation layer through which the first conductive struct