Method of removing organic contaminants from a semiconductor surface
A method for removing organic contaminants from a semiconductor surface whereby the semiconductor is held in a tank and the tank is filled with a fluid such as a liquid or a gas. Organic contaminants, such as photoresist, photoresidue, and dry etched residue, occur in process steps of semiconductor fabrication and at times, require removal. The organic contaminants are removed from the semiconductor surface by holding the semiconductor inside a tank. The method may be practiced using gas phase processing or liquid phase processing. The tank is filled with a gas mixture, a liquid, and/or a fluid, such as water, water vapor, ozone and/or an additive acting as a scavenger (a substance which counteracts the unwanted effects of other constituents of the system).
1 - 49 . (canceled)
50 . A method for removing organic contaminants from a substrate, the organic contaminants resulting from a previous lithographic step, the method comprising the steps of:
contacting at least one side of said substrate with a liquid comprising water, ozone and an additive acting as a scavenger, wherein the proportion of said additive in said liquid is less than 1% molar weight of said liquid; and
maintaining said liquid at a temperature less than the boiling point of said liquid.
51 . A method as recited in claim 50 , wherein said temperature is lower than 100° C.
52 . A method as recited in claim 50 , wherein said liquid is sprayed over at least one side of said substrate.
53 . A method as recited in claim 50 , wherein said temperature is between 16° C. and 99° C.
54 . A method according as recited in claim 53 , wherein the temperature of said liquid is between 20° C. and 90° C.
55 . A method according as recited in claim 54 , wherein the temperature of said liquid is between 60° C. and 80° C.
56 . A method as recited in claim 50 , wherein said liquid is subjected to megasone agitation.
57 . A method as recited in claim 50 , wherein the ozone is bubbled through the liquid.
58 . A method as recited in claim 50 , wherein the organic contamination is a confined layer covering at least part of said substrate.
59 . A method as recited in claim 58 , wherein said confined layer has a thickness in a range of submonolayer coverage and 1 μm.
60 . A method as recited in claim 50 , wherein said additive is acting as OH radical scavenger.
61 . A method as recited in claim 50 , said additive is selected from the group consisting of a carboxylic acid, a phosphonic acid, and salts thereof.
62 . A method as recited in claim 61 , wherein said additive is acetic acid.
63 . A method according to claim 50 , wherein the proportion of said additive in said liquid is less than 0.1% molar weight of said liquid.
64 . A method according to claim 63 , wherein the proportion of said additive in said liquid is less than 0.1% molar weight of said liquid.
65 . A method as recited in claim 50 , wherein the ozone includes ozone bubbles and wherein the ozone bubbles are contacting said organic contaminants.
66 . A method as recited in claim 50 , further comprising the step of rinsing said substrate with a solution.
67 . A method as recited in claim 66 , wherein said solution comprises de-ionised water.
68 . A method as recited in claim 67 , wherein said solution further comprises at least one solution selected from the group consisting of HCl, HF, HNO 3 , CO 2 and O 3 .
69 . A method as recited in claim 66 , wherein said solution is subjected to megasone agitation.
70 . A method as recited in claim 50 , wherein said substrate is a silicon wafer.