Method for cleaning silicon wafer

Patent metadata

Field	Value
Publication number	US-11878329-B2
Application number	US-201816637012-A
Country	US
Kind code	B2
Filing date	Jul 31, 2018
Priority date	Aug 18, 2017
Publication date	Jan 23, 2024
Grant date	Jan 23, 2024

Abstract

A method for cleaning a silicon wafer includes the steps of: supplying hydrofluoric acid onto a surface of the silicon wafer to treat the silicon wafer while rotating at a first rotational rate, stopping the supply of the hydrofluoric acid and shaking off hydrofluoric acid on the surface of the silicon wafer without supplying pure water onto the surface of the silicon wafer while rotating the silicon wafer at a second rotational rate which is the same as or faster than the first rotational rate, and supplying ozone water onto the surface of the silicon wafer to treat the silicon wafer after shaking the hydrofluoric acid off the surface while rotating at a third rotational rate which is faster than the second rotational rate. This method for cleaning a silicon wafer is capable of suppressing adhesion of water marks and particles and enhancing the wafer quality.

First claim

The invention claimed is:

1. A method for cleaning a silicon wafer, comprising, in the following order, the steps of:
supplying hydrofluoric acid onto a surface of the silicon wafer to treat the silicon wafer while rotating at a first rotational rate, thereby removing an oxide film of the surface of the silicon wafer and making the surface a hydrophobic surface,
stopping the supply of the hydrofluoric acid and shaking off hydrofluoric acid present on the hydrophobic surface of the silicon wafer from which the oxide film has been removed without supplying pure water onto the hydrophobic surface of the silicon wafer while rotating the silicon wafer at a second rotational rate which is the same as or faster than the first rotational rate, and
supplying ozone water onto the hydrophobic surface of the silicon wafer from which the oxide film has been removed to treat the silicon wafer after shaking the hydrofluoric acid off the surface while rotating at a third rotational rate which is faster than the second rotational rate, thereby performing reoxidation to the surface of the silicon wafer, wherein
the first rotational rate is 100 rpm or less,
the second rotational rate is 200 rpm or less, and
the third rotational rate is 500 rpm or more.

Assignees

• Shinetsu Handotai Kk

Inventors

• Igarashi Kensaku
• Abe Tatsuo

Classifications

• H10P70/15 Primary

  by wet cleaning only (H10P70/52 takes precedence) · CPC title

• H10P72/0406

  for cleaning followed by drying, rinsing, stripping, blasting or the like · CPC title

• H10P52/00

  Grinding, lapping or polishing of wafers, substrates or parts of devices · CPC title

• H10P72/7618

  characterised by a movable susceptor, stage or support, others than those only rotating on their own vertical axis, e.g. susceptors on a rotating carrousel · CPC title

• H10P14/6309

  of silicon in uncombined form, i.e. pure silicon · CPC title