• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.169-169
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• 2008

To keep pace with scaling trends of CMOS technologies, high-k metal oxides are to be introduced. Due to their high permittivity, high-k materials can achieve the required capacitance with stacks of higher physical thickness to reduce the leakage current through the scaled gate oxide, which make it become much more promising materials to instead of $SiO_2$. As further studying on high-k, an understanding of the relation between the etch characteristics of high-k dielectric materials and plasma properties is required for the low damaged removal process to match standard processing procedure. There are some reports on the dry etching of different high-k materials in ICP and ECR plasma with various plasma parameters, such as different gas combinations ($Cl_2$, $Cl_2/BCl_3$, $Cl_2$/Ar, $SF_6$/Ar, and $CH_4/H_2$/Ar etc). Understanding of the complex behavior of particles at surfaces requires detailed knowledge of both macroscopic and microscopic processes that take place; also certain processes depend critically on temperature and gas pressure. The choice of $BCl_3$ as the chemically active gas results from the fact that it is widely used for the etching o the materials covered by the native oxides due to the effective extraction of oxygen in the form of $BCl_xO_y$ compounds. In this study, the surface reactions and the etch rate of $Al_2O_3$ films in $BCl_3/Cl_2$/Ar plasma were investigated in an inductively coupled plasma(ICP) reactor in terms of the gas mixing ratio, RF power, DC bias and chamber pressure. The variations of relative volume densities for the particles were measured with optical emission spectroscopy (OES). The surface imagination was measured by AFM and SEM. The chemical states of film was investigated using X-ray photoelectron spectroscopy (XPS), which confirmed the existence of nonvolatile etch byproducts.

• Journal of the Korean Vacuum Society
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• v.9 no.3
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• pp.258-262
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• 2000

$YMnO_3$thin films are deposited on Si(100) and $Y_2O_3/Si(100)$ substrate by radio frequency sputtering. The deposition condition of oxygen partial pressure and annealing temperature have significant influences on the preferred orientation of $YMnO_3$film and the size of memory window. The results of x-ray diffraction show that the film deposited in the oxygen partial pressure of 0% is highly oriented along c-axis after annealing at $870^{\circ}C$ for 1 hr in oxygen ambient. However, the films deposited on Si and $Y_2O_3/Si$ in the oxygen partial pressures of 20% show $Y_2O_3$ peak, the excess $Y_2O_3$ in the $YMnO_3$film suppresses the c-axis oriented crystallization. Especially memory windows of the $Pt/YMnO_3/Y_2O_3/Si$ capacitor are 0.67~3.65 V at applied voltage of 2~12 V, which is 3 times higher than that of the film deposited on $Y_2O_3/Si$ in 20% oxygen (0.19~1.21 V) at the same gate voltage because the film deposited in 0% oxygen is well crystallized along c-axis.