The Study on Al2O3 Thin Film Multi-Layer Ceramic Capacitors (MLCC) by Electrode Deposition and Pattering Method
Ji Ho EOM, Soon Gil YOON*
Department of Materials Science and Engineering, Chungnam National University, Daeduk Science Town, 34134, Daejeon, Korea
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Keywords: ALD, MLCC, Al2O3, Evaporator, Photo-lithography
Compared to normal capacitor, MLCC (Multi-layer ceramic capacitor) has large electrode area leads to high capacitance. Al2O3 material is well known dielectric material with low dielectric constant (~ 9.1 @ bulk) and wide bandgap (8.8 eV @ α-Al2O3) provides high quality leakage current density would be suitable for MLCC structure and process studies of capacitor.
In this study, MLCC was fabricated using Al2O3 as dielectric material and Cu as electrode thin films with 1, 2 and 3 layers. Al2O3 films were deposited by atomic layer deposition (ALD) on SiO2/Si substrate using trimethylaluminum (TMA) and DI-water. The Thickness of dielectric Al2O3 films were 40 nm and which were measured by TEM analysis. Cu electrode thin films with thickness of 100 nm were deposited using DC-sputtering and evaporator system to compare capacitance properties. In addition, this films were patterned using shadow mask and photo-lithography method. On the other hand, photo-lithography method for fabrication of MLCC is very easy to align, but it has chemical problem. Dielectric properties of thin films were measured by HP4194A and leakage current of thin films were measured by HP4156B.