PURPOSE: To prevent the lowering of the dielectric constant of a thin film capacitor composed of a lower electrode, a dielectric film, and an upper electrode by suppressing leakage currents generated in the dielectric film of the capacitor by irradiating the film with high energy.
CONSTITUTION: The upper electrode 216 and lower electrode 214 of a capacitor are formed of a hafnium-tantalum alloy. The electrode films of the electrodes 216 and 214 are formed in an argon gas by using a sputtering method using a target made of the alloy. The dielectric film of the capacitor is crystallized by heat-treating the film at 400-700°C in oxygen after a BaTiO3 film is formed by using a sol-gel method. The etching of the electrode films and dielectric film of the capacitor are performed by using a reactive ion etching method. Since the electrodes of the capacitor are formed on the hafnium-tantalum alloy, the electrodes can be formed by the reactive ion etching and a highly reliable stable capacitor characteristic can be obtained.
TOKIMINE YOSHIKAZU
KUROIWA TAKEHARU
MAKITA TETSUO
MIKAMI NOBORU
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