METHOD FOR MANUFACTURING HIGH DIELECTRIC LAYER OF CAPACITOR OF DYNAMIC RANDOM ACCESS MEMORY

摘要

PURPOSE: A method for manufacturing a high dielectric layer of a capacitor of a dynamic random access memory(DRAM) is provided to minimize leakage current by forming barium strontium titanate(BST) layers having different surface morphology. CONSTITUTION: A method for manufacturing a high dielectric layer of a capacitor of a dynamic random access memory(DRAM) comprises four steps. The first step is to form a first barium strontium titanate(BST) layer by evaporating BST material in a first established temperature on a storage node layer forming a lower electrode of the capacitor. The second step is to form a second BST layer by evaporating the BST material in a second established temperature higher than the first established temperature, on the first BST layer. The third step is to form a third BST layer by evaporating the BST layer in a third established temperature higher than the second established temperature. The fourth step is to perform a posterior heat treatment in a temperature higher than the second established temperature after forming a upper electrode of the capacitor on the third BST layer.