公开(公告)号：JP2002033313A

公开(公告)日：2002-01-31

申请号：JP2001161081

申请日：2001-05-29

Applicant: IBM

Inventor： NAEEM MUNIR D ,  MATHAD GANGADHARA S ,  KIM BYEONG YEOL ,  KUDELKA STEPHAN P ,  LEE BRIAN S ,  LI HONG ,  MORALES ELIZABETH ,  PARK YOUNG-JIN ,  RANADE RAJIV M

IPC: H01L21/302 ,  H01L21/3065 ,  H01L21/308 ,  H01L21/8242 ,  H01L27/108

Abstract: PROBLEM TO BE SOLVED: To provide a method of minimizing an RIE lag, which occurs during production of a DT in a DRAM having a large aspect ratio. SOLUTION: Using this method, isotropic etching of a wafer can be prevented and hence a passivation film is formed to such a extent as to require to maintain a profile and shape of a DT in the wafer. The RIE process described here provides a partial DT etched in the wafer to attain a prescribed depth. This passivation film is grown to a certain thickness which is not sufficiently thick to block an opening of the deep-trench. In an alternative method, the passivation film is removed by a non-RIE process. The non-RIE process for removing the film may be wet etching using chemicals, such as hydrofluoric acid (buffered or unbuffered) or the like. Alternatively, a vapor phase of hydrofluoric anhydride or the like and/or un-ionized chemicals may be used. By controlling the film thickness, a prescribed depth of a DT for a high aspect ratio structure can be obtained.

公开(公告)号：WO0193323A3

公开(公告)日：2002-06-27

申请号：PCT/US0115997

申请日：2001-05-18

Applicant: INFINEON TECHNOLOGIES CORP ,  IBM

Inventor： NAEEM MUNIR D ,  LEE BRIAN S ,  MATHAD GANGADHARA S ,  LEE HEON ,  KIM BYEONG YEOL ,  MORALES ELIZABETH ,  KUDELKA STEPHAN P ,  RANADE RAJIV ,  PARK YOUNG-JIN

IPC: H01L21/302 ,  H01L21/3065 ,  H01L21/308 ,  H01L21/8242 ,  H01L27/108 ,  H01L21/311 ,  H01L21/8239

CPC classification number: H01L21/3081 ,  H01L21/3065

Abstract: A method of minimizing RIE lag (i.e., the neutral and ion fluxes at the bottom of a deep trench (DT) created during the construction of the trench opening using a side wall film deposition)) in DRAMs having a large aspect ratio (i.e., > 30:1) is described. The method forms a passivation film to the extent necessary for preventing isotropic etching of the substrate, hence maintaining the required profile and the shape of the DT within the substrate. The RIE process described provides a partial DT etched into a substrate to achieve the predetermined depth. The passivation film is allowed to grow to a certain thickness still below the extent that it would close the opening of the deep trench. Alternatively, the passivation film is removed by a non-RIE etching process. The non-RIE process that removes the film can be wet etched with chemicals, such as hydrofluoric acid (buffered or non buffered) or, alternatively, using vapor phase and/or non-ionized chemicals, such as anhydrous hydrofluoric acid. The controlled thickness of the film allows achieving a predetermined DT depth for high aspect ratio structures

Abstract translation: 最小化RIE滞后的方法（即，在使用侧壁膜沉积的沟槽开口的构造期间产生的深沟槽（DT）的底部处的中性和离子通量））具有大纵横比的DRAM（即， > 30：1）。 该方法形成钝化膜，以防止基板的各向同性蚀刻所必需的程度，从而将所需的轮廓和DT的形状保持在基板内。 所述的RIE工艺提供了蚀刻到衬底中以实现预定深度的部分DT。 允许钝化膜生长到一定厚度，仍然低于其将关闭深沟槽的开口的程度。 或者，通过非RIE蚀刻工艺去除钝化膜。 可以用诸如氢氟酸（缓冲或非缓冲）的化学品或者使用蒸气相和/或非电离化学物质如无水氢氟酸来湿法蚀刻除去膜的非RIE工艺。 膜的受控厚度允许实现高纵横比结构的预定DT深度