公开(公告)号：US09508880B2

公开(公告)日：2016-11-29

申请号：US13649398

申请日：2012-10-11

Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.

Inventor： Takashi Hirose ,  Ryosuke Motoyoshi

IPC: H01L29/12 ,  H01L29/06 ,  H01L29/04 ,  H01L33/00 ,  H01L31/0236

CPC classification number: H01L31/02363 ,  Y02E10/50

Abstract: It is an object to provide a method for processing a silicon substrate that can reduce surface reflectance as much as possible. The method includes a first step of forming a thin film including a metal having higher electronegativity than silicon and having a plurality of openings on a silicon substrate, a second step of soaking the silicon substrate subjected to the first step in a hydrofluoric acid solution containing oxidizer, and a third step of soaking the silicon substrate subjected to the second step in an ammonia aqueous solution containing oxidizer. By performing the steps in the above order, a minute uneven structure is formed on a surface of the silicon substrate to reduce the reflectance.

Abstract translation: 本发明的目的是提供一种可以尽可能地减少表面反射率的硅衬底的处理方法。 该方法包括：形成薄膜的第一步骤，该薄膜包括具有比硅更高的电负性且在硅衬底上具有多个开口的金属，第二步是将经过第一步骤的硅衬底浸入含有氧化剂的氢氟酸溶液中 以及将经过第二工序的硅衬底浸渍在含有氧化剂的氨水溶液中的第三工序。 通过按照上述顺序执行步骤，在硅衬底的表面上形成微小的凹凸结构以降低反射率。