公开(公告)号：US06897107B2

公开(公告)日：2005-05-24

申请号：US10720490

申请日：2003-11-24

申请人： Rama Divakaruni ,  Thomas W. Dyer ,  Rajeev Malik ,  Jack A. Mandelman ,  Venkatachajam C. Jaiprakash

发明人： Rama Divakaruni ,  Thomas W. Dyer ,  Rajeev Malik ,  Jack A. Mandelman ,  Venkatachajam C. Jaiprakash

IPC分类号： H01L21/316 ,  H01L21/318 ,  H01L21/8242 ,  H01L21/20

CPC分类号： H01L27/10864 ,  H01L21/31612 ,  H01L21/3185 ,  H01L27/10867

摘要： A structure and method which enables the deposit of a thin nitride liner just before Trench Top Oxide TTO (High Density Plasma) HDP deposition during the formation of a vertical MOSFET DRAM cell device. This liner is subsequently removed after TTO sidewall etch. One function of this liner is to protect the collar oxide from being etched during the TTO oxide sidewall etch and generally provides lateral etch protection which is not realized in the current processing scheme. The process sequence does not rely on previously deposited films for collar protection, and decouples TTO sidewall etch protection from previous processing steps to provide additional process flexibility, such as allowing a thinner strap Cut Mask nitride and greater nitride etching during node nitride removal and buried strap nitrided interface removal. Advantageously, the presence of the nitride liner beneath the TTO reduces possibility of TTO dielectric breakdown between the gate and capacitor node electrode of the vertical MOSFET DRAM cell, while assuring strap diffusion to gate conductor overlap.

摘要翻译： 在垂直MOSFET DRAM单元器件形成期间，能够在沟槽顶氧化物TTO（高密度等离子体）HDP沉积之前沉积薄氮化物衬垫的结构和方法。 随后在TTO侧壁蚀刻之后移除该衬垫。 该衬垫的一个功能是在TTO氧化物侧壁蚀刻期间保护套环氧化物不被蚀刻，并且通常提供在当前处理方案中未实现的横向蚀刻保护。 工艺顺序不依赖于以前沉积的膜用于套环保护，并且将TTO侧壁蚀刻保护与先前的处理步骤解耦以提供附加的工艺灵活性，例如在节点氮化物去除期间允许更薄的带切割掩模氮化物和更大的氮化物蚀刻和掩埋带 氮化界面去除。 有利地，在TTO之下的氮化物衬垫的存在降低了垂直MOSFET DRAM单元的栅极和电容器节点电极之间的TTO介质击穿的可能性，同时确保带扩散到栅极导体重叠。