METHOD FOR FORMING FERROELECTRIC LAYER OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming a ferroelectric layer of a semiconductor device is provided to improve fatigue characteristic, leakage current characteristic and retention characteristic, by compensating for Pb lost by volatility and diffusion due to an Pb ion implantation process, by expanding crystal grains of a ferroelectric by a high-temperature heat treatment process and by reducing an interfacial area of crystal grains. CONSTITUTION: A ferroelectric layer composed of a ferroelectric phase(10), a pyrochlore phase and an amorphous phase is formed on a substrate at a temperature scope of 150-400 deg.C. Excessive Pb ions are implanted into the ferroelectric layer. A heat treatment process is performed to crystallize the pyrochlore phase to a ferroelectric phase while a crystal growth is generated to make respective ferroelectric phases contact each other.