Method to achieve STI planarization
    1.
    发明授权
    Method to achieve STI planarization 失效
    实现STI平坦化的方法

    公开(公告)号:US06869857B2

    公开(公告)日:2005-03-22

    申请号:US10002987

    申请日:2001-11-30

    摘要: A new method of forming shallow trench isolations without using CMP is described. A plurality of isolation trenches are etched through an etch stop layer into the semiconductor substrate leaving narrow and wide active areas between the trenches. An oxide layer is deposited over the etch stop layer and within the trenches using a high density plasma chemical vapor deposition process (HDP-CVD) having a deposition component and a sputtering component wherein after the oxide layer fills the trenches, the deposition component is discontinued while continuing the sputtering component until the oxide layer is at a desired depth. In one method, the oxide layer overlying the etch stop layer in the wide active areas is etched away. The etch stop layer and oxide layer residues are removed to complete planarized STI regions. In another method, a second etch stop layer is deposited over the oxide layer using a HDP-CVD process whereby the second etch stop layer is sputtered away over the oxide layer overlying the first etch stop layer in the narrow active areas and whereby the second etch stop layer remains in the wide active areas. The second etch stop layer over the oxide layer in the wide active areas is etched away. The oxide layer overlying the first etch stop layer in the narrow and wide active areas is etched away. The first and second etch stop layers are removed to complete STI regions.

    摘要翻译: 描述了不使用CMP形成浅沟槽隔离的新方法。 通过蚀刻停止层将多个隔离沟槽蚀刻到半导体衬底中,在沟槽之间留下窄而宽的有源区。 使用具有沉积组分和溅射组分的高密度等离子体化学气相沉积工艺(HDP-CVD),在蚀刻停止层和沟槽内沉积氧化物层,其中在氧化物层填充沟槽之后,沉积组分被中断 同时继续溅射组分直到氧化物层处于期望的深度。 在一种方法中,覆盖在宽有效区域中的蚀刻停止层上的氧化物层被蚀刻掉。 去除蚀刻停止层和氧化物层残余物以完成平坦化的STI区域。 在另一种方法中,使用HDP-CVD工艺在氧化物层上沉积第二蚀刻停止层,由此将第二蚀刻停止层溅射在覆盖窄有源区域中的第一蚀刻停止层上的氧化物层上,并且由此第二蚀刻 停止层保留在广泛的有效区域。 在宽的有源区域中的氧化物层上的第二蚀刻停止层被蚀刻掉。 覆盖在窄且宽的有源区域中的第一蚀刻停止层上的氧化物层被蚀刻掉。 去除第一和第二蚀刻停止层以完成STI区域。