Post-polish cleaning of oxidized substrates by reverse colloidation

Claim 2

In a process for polishing an oxide film formed over a silicon substrate utilizing a colloidal suspension of particles, a post-polishing method for cleaning said substrate to remove residual particles adhering to the surface of said substrate, said method comprising the steps of: placing said substrate in a solution having a sufficiently high alkalinity to electrochemically repel said residual particles from said substrate; removing said substrate from said solution.

Claim 3

The method as described in claim 1 wherein said particles comprise silica particles.

Claim 4

The method as described in claim 2 wherein the PH of said solution is approximately 10.

Claim 5

The method as described in claim 3 wherein said solution is a KOH-based solution.

Claim 6

The method as described in claim 4 further comprising the steps of: rinsing said substrate in de-ionized water; ultrasonically cleaning said substrate in de-ionized water; and drying said substrate.

Claim 7

In a semiconductor polishing process utilizing an apparatus which forcibly presses a semiconductor substrate against a pad coated with a slurry containing abrasive particles suspended in a liquid, said particles having a characteristic zeta potential of a certain plarity, and said pad and said substrate being set in relative movements to one another to facilitate planarization of a dielectric layer formed on said substrate, a post-polishing method for cleaning said substrate to remove remnant slurry particles adhering to the surface of said substrate comprising the steps of: placing said substrate in a PH-controlled solution to electrochemically repel said residual particles from said substrate, the PH level of said solution being adjusted to said certain polarity such that if said zeta potential is negative said PH level is greater than 7, and if said zeta potential is positive said PH level is less than 7; removing said substrate from said solution.

Claim 8

In a semiconductor polishing process utilizing an apparatus which forcibly presses a semiconductor substrate against a pad coated with a slurry containing abrasive particles suspended in a liquid, said particles having a characteristic zeta potential of a certain plarity, and said pad and said substrate being set in relative movements to one another to facilitate planarization of a dielectric layer formed on said substrate, a post-polishing method for cleaning said substrate to remove remnant slurry particles adhering to the surface of said substrate comprising the steps of: placing said substrate in a PH-controlled solution to electrochemically repel said residual particles from said substrate, the PH level of said solution being adjusted to said certain polarity such that if said zeta potential is negative said PH level is greater than 7, and if said zeta potential is positive said PH level is less than 7; removing said substrate from said solution.

Claim 9

The method as described in claim 6 wherein said particles comprise silica particles.

Claim 10

The method as described in claim 7 wherein said PH level is approximately 10.

Claim 11

The method as described in claim 8 wherein said solution is a KOH-based solution.

Claim 12

The method as described in claim 9 further comprising the steps of: rinsing said substrate in de-ionized water; ultrasonically cleaning said substrate in de-ionized water; and drying said substrate.