METHOD FOR FORMING TRENCH CAPACITOR WITHIN TRENCH HAVING HIGH ASPECT RATIO AND TRENCH CAPACITOR

摘要

PURPOSE: A method for forming trench capacitor within high-aspect-ratio trench and a trench capacitor are provided to completely fill a deep trench. CONSTITUTION: A method for forming trench capacitor within a high-aspect-ratio trench comprises (a) a step depositing a filling layer(30') on top surface of a wafer and trenches(10,10'), and (b) a step heat-treating the filling layer under the temperature more than melting point of the filling layer and less than melting point of the wafer. The filling layer consists of material among group consisted of germanium and silicon-germanium alloy. On the top of the filling layer, a cap layer(36) is deposited between the steps(a,b).