Nucleation enhancing buffer layers

For this study pzt films with (111) and (100) orientation grown on Pt (111) bottom electrodes by chemical solution deposition were used. In the case of (100) orientation a 10 nm lead titanate buffer layer was used in order to enhance (100) nucleation. The films with Zr/Ti ratio of 40/60 contained dopants including Ca, Sr and La [20]. The thickness of (111) and (100) oriented films was 135 nm and 150 nm, respectively. IrCL top electrodes with different sizes down to 0.5x 0.5 pm2 have been patterned by reactive ion etching. The electroded pzt film was etched approximately to a half of its original thickness. 

Nanocrystalline cubic SiC (P-SiC) films were grown on silicon (100) substrate by catalytic chemical vapor deposition (Cat-CVD) at a temperature as low as 300°C with a pre-carbonization process. To enhance nucleation density of P-SiC, a buffer layer was made by carbonizing the substrate surface. From the comparison between both carbonized sample and non-carbonized sample, the precarbonization process has beneficial effects on the growth of nanociystalline p-SiC films. Mechanistic interpretations are given to explain the carbonization process and catalyzing deposition process. 

The enhancement of nucleation and adhesion of diamond films has been achieved on Cu, stainless steel and Si using a pulsed laser irradiation pretreatment, followed by HFCVD.t l A thin buffer layer of a-C, WC or cBN was first deposited on the substrates by pulsed laser evaporation, followed by pulsed laser irradiation. For the Cu substrates, diamond nucleation densities on the a-C overlayer and WC (or cBN) buffer layer were... 

Pulsed laser irradiation of a thin buffer layer of a-C, WC or cBN deposited on Cu, stainless steel, and Si substrates leads to enhancement of nucleation and adhesion of diamond film.s on the substrates. The irradiation may convert a portion of the a-C on the surface into diamond or result in the formation of a reaction product that cilitates diamond nucleation. 

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