Bowl for liquid spray processing machine

Abstract

A spray processing machine for processing silicon wafers in the manufacture of integrated circuit chips the bowl defining the processing chamber being formed of molded plastic of a type which is highly inert to the deteriorating effects of highly active chemicals such as hydrochloric and hydrofluoric acid and similar highly active chemicals. The molded bowl has upright side walls with a cylindrical configuration and flat areas on the inner periphery to accommodate mounting spray posts on an upright position. The molded plastic housing also has a base wall which is peripherally downwardly spiraling configuration toward the drain port and from the highest portion of the base wall, also immediately adjacent the drain port; there being a step in the base wall defining a riser face facing opposite to the direction of the slope of the base wall and also facing opposite to the direction of rotation of the rotor in the processing chamber which carriers the wafers being processed. The base wall of the molded housing also defining integrally therewith, a rinsing water spray port to spray water against the bottom side of the turntable; and integrally formed an annular ribs spaced from each other concentric of the rotation axis to act with similar ribs on the turntable to define a labyrinth against flow of liquids inwardly toward the centrally disposed shaft.