| 摘要 |
PURPOSE: To increase the effective area of a capacitor, while a high dielectric thin film is utilized to enable the manufacture of a large-capacitance capacitor by a method wherein the lower electrode of the capacitor is formed using a tungsten film of roughened surface. CONSTITUTION: First, a TiN film 6 is formed on a semiconductor substrate 1. The film 6 is patterned into a lower electrode of a capacitor, and tungsten is deposited on the surface of the film 6 at a temperature of 200 to 650 deg.C. In this case, a delay of a depositing initial time of about 7 to 10 minutes exists at a temperature of about 450 deg.C under a chemical action of WF6 -H2 , the nuclei of the tungsten is formed at a certain specified site on the surface of the film 6 during this time and a tungsten film 7 is insularly formed. As a result, a high dielectric thin film 8 is formed as a composite thin film, which consists of the film 6 and the tungsten film 7 having a roughened surface for forming a capacitor, whereby a large-capacitance capacitor can be obtained. |
