Abstract:
PURPOSE: A ferroelectric random access memory device and a fabrication method thereof are provided to stabilize an encapsulating barrier layer formed of a metallic oxide. CONSTITUTION: In the ferroelectric memory device, a gate insulating layer(102) and a gate electrode(104) are formed on a semiconductor substrate(100), and a source and a drain regions(106,107) are formed in the substrate(100). An interlayer dielectric layer(108) is then formed on a resultant structure and patterned to form a contact hole exposing the source or the drain region(106,107). After a contact plug(110) is formed in the contact hole, a lower electrode(112) is formed over a resultant structure. Then, a ferroelectric layer(114) and an upper electrode(116) are sequentially formed thereon. The lower and the upper electrodes(112,116) and the ferroelectric layer(114) are patterned to form a capacitor cell unit. Thereafter, the encapsulating barrier layer(118) is formed of the metallic oxide on a resultant structure and then treated with plasma(120) using oxygen or hydrogen gas to enhance an insulating property thereof. Therefore, the encapsulating barrier layer(118) is stabilized.
Abstract:
PURPOSE: A method for cleaning a PZT thin film is provided to exactly remove only damaged surface of the PZT thin film by slowing an etching speed depend on concentration of HF solution. CONSTITUTION: The method comprises the step of etching a surface of a PZT thin film(2) by dipping the PZT thin film(2) into an etching solution composed of BOE(buffered oxide etchant) such as HF and acetic acid. The acetic acid used for removing Pb components and the HF used for removing Ti and Zr components. To be slow etching speed (that is, increasing cleaning effect instead of etching effect), the etching solution further comprises an alcohol. The alcohol is a member selected from the group consisting of methanol, ethanol or propanol.
Abstract:
본 발명은 전기적 특성이 개선된 PZT 박막 캐패시터의 제조 방법에 관한 것이다. 본 발명에 따른 PZT 박막의 제조 방법은 씨앗층과 급속 어닐링(RTA) 공정에 의한 2단 공정을 도입함으로써 포화분극, 잔류분극, 잔류분극량의 증가 및 스윗칭 전압의 강하를 가져와 한층 더 메모리 소자로서의 특성이 증가되도록 한다. 또한 이와같이 RTA 공정으로 만들어진 박막은 입자가 매우 미세하며 기판 전체에 걸쳐골고루 작은 입자들로 구성되어 있어 균일한 박막의 전기적 특성을 나타낼 뿐 만 아니라 열처리 시간을 단축시킬 수 있으며, 이와 같은 짧은 열처리 공정은 장기간의 열처리시 우려가되는 Pb성분과 Si과의 상호 반응 가능성도 줄일 수 있는 장점이 있다.