Pretreatment method for photoresist wafer processing

摘要

Certain embodiments herein relate to methods and apparatus for processing a partially fabricated semiconductor substrate in a remote plasma environment. The methods may be performed in the context of wafer level packaging (WLP) processes. The methods may include exposing the substrate to a reducing plasma to remove photoresist scum and/or oxidation from an underlying seed layer. In some cases, photoresist scum is removed through a series of plasma treatments involving exposure to an oxygen-containing plasma followed by exposure to a reducing plasma. In some embodiments, an oxygen-containing plasma is further used to strip photoresist from a substrate surface after electroplating. This plasma strip may be followed by a plasma treatment involving exposure to a reducing plasma. The plasma treatments herein may involve exposure to a remote plasma within a plasma treatment module of a multi-tool electroplating apparatus.

主权项

1. A method of removing photoresist scum and electroplating metal into photoresist features, the method comprising:
(a) receiving a substrate in a multi-tool electroplating apparatus, the multi-tool electroplating apparatus comprising:
(i) at least one plasma treatment module comprising a plasma treatment chamber and a plasma generation chamber connected to the plasma treatment chamber; and(ii) at least one electroplating module comprising an electroplating chamber;wherein the substrate comprises:(i) a metal seed layer, and(ii) a layer of photoresist over and directly in contact with the metal seed layer, wherein the layer of photoresist comprises photoresist features patterned therein, and wherein a bottom of the photoresist features comprise photoresist scum; (b) generating a reducing plasma from a reducing plasma generation gas in the plasma generation chamber; (c) flowing the reducing plasma from the plasma generation chamber into the plasma treatment chamber to thereby expose the substrate to the reducing plasma, react the photoresist scum with the reducing plasma, and remove at least a portion of the photoresist scum; and (d) transferring the substrate to the electroplating module and electroplating metal on the metal seed layer in the photoresist features.