Abstract: An improved, process compatible fastener is especially useful for securing a member, such as a wafer clamp ring, to an assembly for use in a process environment. The fastener is of a simple design, such that it is readily manufactured, and such that it is not a source of contamination. In particular, an integrated fastener includes both a metal fastener and a cone shaped metal lock washer within a single fastener assembly, such that a single fastener is used for accomplish the function of a screw and a washer. All surfaces of the fastener that are exposed within the process environment are encapsulated in a process compatible material. In this way, the fastener may be secured in the process environment in a single operation without leaving any gaps or partially exposed surfaces that may introduce contaminants into the process environment, such that the integrated fastener also provides the function of a process compatible cap.