Removal of charged defects from metal oxide-gate stacks
    1.
    发明授权
    Removal of charged defects from metal oxide-gate stacks 失效
    从金属氧化物 - 栅极堆叠中去除带电的缺陷

    公开(公告)号:US07488656B2

    公开(公告)日:2009-02-10

    申请号:US11119310

    申请日:2005-04-29

    IPC分类号: H01L21/336

    摘要: The present invention provides a method for removing charged defects from a material stack including a high k gate dielectric and a metal contact such that the final gate stack, which is useful in forming a pFET device, has a threshold voltage substantially within the silicon band gap and good carrier mobility. Specifically, the present invention provides a re-oxidation procedure that will restore the high k dielectric of a pFET device to its initial, low-defect state. It was unexpectedly determined that by exposing a material stack including a high k gate dielectric and a metal to dilute oxygen at low temperatures will substantially eliminate oxygen vacancies, resorting the device threshold to its proper value. Furthermore, it was determined that if dilute oxygen is used, it is possible to avoid undue oxidation of the underlying semiconductor substrate which would have a deleterious effect on the capacitance of the final metal-containing gate stack. The present invention also provides a semiconductor structure that includes at least one gate stack that has a threshold voltage within a control range and has good carrier mobility.

    摘要翻译: 本发明提供了一种用于从包括高k栅极电介质和金属接触的材料堆叠中去除带电缺陷的方法,使得用于形成pFET器件的最终栅极堆叠具有基本上在硅带隙内的阈值电压 和良好的载波移动性。 具体地说,本发明提供了将pFET器件的高k电介质恢复到其初始低缺陷状态的再氧化过程。 意外地确定,通过暴露包括高k栅极电介质和金属的材料堆以在低温下稀释氧将基本上消除氧空位,使装置阈值达到适当的值。 此外,确定如果使用稀释氧,则可以避免对最终含金属的栅极叠层的电容产生有害影响的下面的半导体衬底的不适当的氧化。 本发明还提供一种半导体结构,该半导体结构包括至少一个栅极堆叠,其具有在控制范围内的阈值电压并具有良好的载流子迁移率。