公开(公告)号：US06271117B1

公开(公告)日：2001-08-07

申请号：US08880952

申请日：1997-06-23

申请人： George Meng Jaw Cherng

发明人： George Meng Jaw Cherng

IPC分类号： H01L214763

CPC分类号： H01L21/76895 ,  H01L21/76804

摘要： The invention has two embodiments for forming a contact plug having large nail shaped landing pad. The large pad areas increase the overlay tolerances. The first embodiment comprises forming first 20 and second 24 insulating layers over a semiconductor structure. A first photoresist layer 28 with a first opening is formed over the second insulating layer 24. The second insulating layer 24 is isotropically etched using an etchant with a high selectivity thereby forming a disk shaped opening 26A. The disk shaped opening is used to define the large nail shaped landing pad. The first insulating layer 20 is etched using a dry etch thereby forming a nail shaped contact opening 26. The opening is filled with polysilicon to form the nail shaped conductive plug 36. The second embodiment begins by forming a first insulating layer 40 over a semiconductor structure. A first photoresist layer 44 with a first opening is formed over the first insulating layer 24. The first insulating layer is isotropically etched to form a half spherical hole. The first insulating layer 40 is then anisotropically etched; and forming a rounded nail shaped contact hole 50. The hole 50 is filled thereby forming the rounded nail shaped conductive plug 58.

摘要翻译： 本发明具有形成具有大指甲形着陆垫的接触塞的两个实施例。 大焊盘区域增加覆盖公差。 第一实施例包括在半导体结构上形成第一绝缘层20和第二绝缘层24。 具有第一开口的第一光致抗蚀剂层28形成在第二绝缘层24之上。使用蚀刻剂以高选择性进行各向同性蚀刻的第二绝缘层24，从而形成盘形开口26A。 盘形开口用于限定大型指甲形着陆垫。 使用干蚀刻蚀刻第一绝缘层20，从而形成钉状接触开口26.该开口填充有多晶硅以形成指甲形导电插塞36.第二实施例开始于在半导体结构上形成第一绝缘层40 。 具有第一开口的第一光致抗蚀剂层44形成在第一绝缘层24上。第一绝缘层被各向同性蚀刻以形成半球形孔。 然后对第一绝缘层40进行各向异性蚀刻; 并且形成圆形的指甲形接触孔50.填充孔50，从而形成圆形的钉状导电塞58。