Method of manufacturing ferroelectric bismuth layered oxides

    公开(公告)号:US5519566A

    公开(公告)日:1996-05-21

    申请号:US403489

    申请日:1995-03-14

    摘要: A semiconductor manufacturing method is directed to forming a ferroelectric film, and in particular a ferroelectric film of the bismuth layer structure type, that has a significant component of reversible polarization perpendicular to the plane of the electrodes. The manufacturing method is conducted at low temperatures on commercially suitable electrodes and is compatible with conventional CMOS fabrication techniques. A ferroelectric strontium-bismuth-tantalate ("SBT") film is formed using two sputtering targets. A first sputtering target is comprised primarily of bismuth oxide (Bi.sub.2 O.sub.3) and a second sputtering target is comprised primarily of SBT. An initial layer of bismuth oxide is formed on the bottom electrode of a ferroelectric capacitor stack. The initial layer of bismuth oxide is directly followed by a sputtered layer of SBT. A second layer of bismuth oxide is then applied and the layers are alternated in a "layer cake" fashion containing a plurality of layers until a desired thickness of the film is attained. At the end of the deposition, a crystallization anneal is performed to make the film ferroelectric. Once the ferroelectric film is in place, the top electrode is formed and the remaining processing steps are completed.

    Method of manufacturing ferroelectric bismuth layered oxides
    4.
    发明授权
    Method of manufacturing ferroelectric bismuth layered oxides 失效
    铁电铋层状氧化物的制造方法

    公开(公告)号:US5426075A

    公开(公告)日:1995-06-20

    申请号:US259870

    申请日:1994-06-15

    摘要: A semiconductor manufacturing method is directed to forming a ferroelectric film, and in particular a ferroelectric film of the bismuth layer structure type, that has a significant component of reversible polarization perpendicular to the plane of the electrodes. The manufacturing method is conducted at low temperatures on commercially suitable electrodes and is compatible with conventional CMOS fabrication techniques. A ferroelectric strontium-bismuth-tantalate ("SBT") film is formed using two sputtering targets. A first sputtering target is comprised primarily of bismuth oxide (Bi.sub.2 O.sub.3) and a second sputtering target is comprised primarily of SBT. An initial layer of bismuth oxide is formed on the bottom electrode of a ferroelectric capacitor stack. The initial layer of bismuth oxide is directly followed by a sputtered layer of SBT. A second layer of bismuth oxide is then applied and the layers are alternated in a "layer cake" fashion containing a plurality of layers until a desired thickness of the film is attained. At the end of the deposition, a crystallization anneal is performed to make the film ferroelectric. Once the ferroelectric film is in place, the top electrode is formed and the remaining processing steps are completed.

    摘要翻译: 半导体制造方法涉及形成具有垂直于电极平面的可逆极化的显着成分的铁电体膜,特别是铋层结构型的铁电体膜。 该制造方法在商业合适的电极上在低温下进行,并且与传统的CMOS制造技术兼容。 使用两个溅射靶形成铁电锶 - 钽酸铋(“SBT”)膜。 第一溅射靶主要由氧化铋(Bi 2 O 3)组成,第二溅射靶主要由SBT组成。 在铁电电容器叠层的底部电极上形成氧化铋的初始层。 氧化铋的初始层之后是SBT的溅射层。 然后施加第二层氧化铋,并且这些层以包含多个层的“层块”方式交替转换,直到达到所需的膜厚度。 在沉积结束时,进行结晶退火以使膜成为铁电体。 一旦铁电薄膜就位,就形成顶部电极,并完成其余的处理步骤。