Self aligning lift mechanism

摘要

A particular configuration of a compact self-aligning lift mechanism is provided for lifting the stem of a pedestal in a processing chamber while minimizing process anomalies due to geometric misalignment and binding of moving pieces. The force associated with supporting a stem in a processing chamber is routed through a first arm through a base portion of a carrier bracket where it engages a linear bearing such that the truck and track of the linear bearing absorb all forces riot aligned with the bearing. A second arm extending from the base portion, for example through a set of slots adjacent to the bearing track support member, is attached to a lift mechanism which can oppose the force from the pedestal stem such that the displacements of the first and second arms are predictable based on the force on that arm. A compliant nut is used so that the drive screw can be somewhat misaligned with the linear bearing track without causing binding, misalignment, or non-repeatability of substrate positioning during processing.