Substrate cleaning device and substrate cleaning method
A substrate cleaning device includes an upper holding device. The upper holding device holds a substrate in a horizontal attitude without rotating the substrate, while being in contact with an outer peripheral end of the substrate. A lower-surface brush wetted with a cleaning liquid is pressed against a lower-surface center region of the substrate held by the upper holding device. In this state, the lower-surface brush is rotated or moved with respect to the lower-surface center region of the substrate. Thus, the lower-surface center region of the substrate is cleaned.
1 . A substrate cleaning device that cleans an upper surface and a lower surface of a substrate with use of a cleaning liquid, comprising:
a first substrate holder that holds the substrate in a horizontal attitude while not rotating the substrate by abutting against a plurality of portions of an outer peripheral end of the substrate;
a second substrate holder configured to contact a lower-surface center region of the substrate while holding and rotating the substrate;
a first lower-surface liquid supplier configured to eject the cleaning liquid towards a bottom surface of the substrate when the substrate is held by said first substrate holder;
a cleaning brush configured to come into contact with the lower surface of the substrate;
a brush driver configured to press the cleaning brush against the lower surface of the substrate held by the first substrate holder and move the cleaning brush relative to the substrate held by the first substrate holder; and
a controller, wherein
the controller controls the first lower-surface liquid supplier to have the first lower-surface liquid supplier eject the cleaning liquid onto the bottom surface of the substrate such that some of the ejected cleaning liquid falls from the bottom surface onto the cleaning brush in order to wet the cleaning brush, wherein the controller controls the brush driver such that the wetted cleaning brush is moved into contact with the lower-surface center region of the substrate, and wherein, after the cleaning brush is used to clean the lower-surface center region of the substrate, the controller controls the second substrate holder to come into contact with lower-surface center region of the substrate such that the substrate can be rotated by the second substrate holder.
2 . The substrate cleaning device according to claim 1 , wherein the second substrate holder rotates the substrate about an axis extending in an up-and-down direction while holding the substrate in a horizontal attitude by sucking the lower-surface center region of the substrate; and the apparatus further comprises:
an upper-surface liquid supplier that supplies the cleaning liquid to the upper surface of the substrate held by the second substrate holder; and
a second lower-surface liquid supplier that supplies the cleaning liquid to a lower-surface outer region surrounding the lower-surface center region of the substrate held by the second substrate holder, wherein
the brush driver is configured to further press the cleaning brush against the lower-surface outer region of the substrate held by the second substrate holder, and
the controller controls the second substrate holder, the upper-surface liquid supplier, the second lower-surface liquid supplier and the brush driver such that the cleaning brush is pressed against the lower-surface outer region of the substrate while the cleaning liquid is supplied to the upper surface of the substrate rotated by the second substrate holder and the cleaning liquid is supplied to the lower-surface outer region of the substrate.
3 . The substrate cleaning device according to claim 1 , wherein
the cleaning brush is a lower-surface brush used to clean the lower surface of the substrate, and
the lower-surface brush includes
a base portion having a flat surface directed upwardly, and
a first cleaning portion provided at the flat surface of the base portion so as to project upwardly from the flat surface of the base portion and extend along an outer edge of the base portion.
4 . The substrate cleaning device according to claim 3 , wherein
the lower-surface brush further includes a second cleaning portion provided at the flat surface of the base portion so as to project upwardly from the flat surface of the base portion and extend in one direction through a geometric center of the base portion in plan view.
5 . A substrate cleaning method of cleaning an upper surface and a lower surface of a substrate with use of a cleaning liquid, including the steps of:
holding the substrate in a horizontal attitude while not rotating the substrate by using a first substrate holder that abuts against a plurality of portions of an outer peripheral end of the substrate;
ejecting the cleaning liquid towards the lower surface of the substrate while the substrate is held by the first substrate holder, wherein some of the ejected cleaning liquid falls from the lower surface of the substate onto the cleaning brush in order to wet the cleaning brush;
pressing the wetted cleaning brush against the lower surface of the substrate so that the wetted cleaning brush comes into contact with the lower surface of the substrate held by the first substrate holder; and
moving the wetted cleaning brush relative to the substrate held by the first substrate holder; and
after the moving of the wetted cleaning brush relative to the substrate held by the first substrate holder, bringing a second substrate holder into contact with the lower surface of the substrate, wherein the second substrate holder is configured to hold and rotate the substrate.
6 . The substrate cleaning method according to claim 5 , further including the steps of:
rotating the substrate about an axis extending in an up-and-down direction while holding the substrate in a horizonal attitude by using the second substrate holder, wherein the second substrate holder sucks a lower-surface center region of the substrate;
supplying the cleaning liquid to the upper surface of the substrate held and rotated by the second substrate holder; and
supplying the cleaning liquid to a lower-surface outer region surrounding the lower-surface center region of the substrate held and rotated by the second substrate holder with the cleaning liquid supplied to the upper surface of the substrate, wherein
the pressing and moving steps include moving the cleaning brush on the lower-surface outer region of the substrate while pressing the cleaning brush against the lower-surface outer region of the substrate with the cleaning liquid supplied to the upper surface of the substrate rotated by the second substrate holder and with the cleaning liquid supplied to the lower-surface outer region of the substrate.
7 . The substrate cleaning method according to claim 5 , wherein
the cleaning brush is a lower-surface brush used to clean the lower surface of the substrate, and
the lower-surface brush includes
a base portion having a flat surface directed upwardly, and
a first cleaning portion provided at the flat surface of the base portion so as to project upwardly from the flat surface of the base portion and extend along an outer edge of the base portion.
8 . The substrate cleaning method according to claim 7 , wherein
the lower-surface brush further includes a second cleaning portion provided at the flat surface of the base portion so as to project upwardly from the flat surface of the base portion and extend in one direction through a geometric center of the base portion in plan view.