Ceramic thick films

Feature Cofired Ceramic Thick Film Thin Film... 

Schierbaum K. D., Weimar U., and Gopel W., Comparison of ceramic thick-film and thin-film chemical sensors based upon Sn02, Sens. Actuators B, 7, 709-716, 1992. 

Ceramic thick films are most often used in applications where their electrical properties are exploited. In these applications, the ceramic thick films usually serve as either insulators, resistors, or capacitors. However, in many of these applications, especially those involving multilayer ceramics made from tape-cast films, the mechanical or thermal properties of the ceramic must also be considered. 

Ceramic thick films made by tape casting are used to fabricate multilayer ceramic (MLC) devices. By far the two most important such devices are MLC capacitors and MLC packages for integrated circuits. In MLC capacitors, layers of phase-pure, high-dielectric constant ceramic alternate with metal electrode layers. In MLC packages, the ceramic phase serves as electrical insulation between conducting metal lines and may contain a relatively small amount of glass. 

In many respects, the characterization of the consolidation of ceramic thick films is similar to that of bulk ceramics, which is discussed in Chapter 5. However, several important features of thick films make them unique. Their small thicknesses make some characterization techniques inapplicable and sample preparation for other characterization techniques more difficult. Also, in both screen-printed and tape-cast structures, the ceramic thick film is in intimate contact with one or more dissimilar materials such as a metal. This contact can produce interdiffusion and reactions between these phases. 

The characterization of ceramic thick films requires the use of special techniques in addition to those normally used to characterize bulk ceramics. This chapter has focused on these special techniques. The reader is referred to the following chapter for more information on the standard characterization techniques for ceramics, since many of them are also applicable to thick films. 

ZnO 200-600 Ceramic Thick film Thin film Ni,Lip,Erp3,WO, CaO, AI3O3, Inp3, SnOj 03,03,C0,H3,CH, NH3,N03,CP50H... 

Screen or stencil print Polymer thick-film addition (PTE) Ceramic thick-film addition (CTF)... 

The sections below summarize firstly the metalization of conductive materials on alumina ceramics (thick film processing and HTCC) which has a strong connection with the metalization of LTCC conductive materials, and further explain in detail the requirements of the conductive materials above. 

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