an apparatus for use within a process chamber is provided . the apparatus includes a liner adapted to cover the sidewalls of the process chamber , with apertures corresponding to various inlets and outlets in the process chamber . in addition , the liner has one or more apertures on its bottom surface , which allow particles to pass through the liner . the liner is designed to be shorter in height than the sidewalls of the process chamber . this allows the liner to be placed within the chamber such that its bottom surface is above the floor of the process chamber . this minimizes the possibility of particles that have fallen onto the process chamber floor becoming re - suspended at a later time . according to a second aspect of the disclosure , a bottom liner is provided . this liner can be used in conjunction with a conventional liner or in a process chamber without a liner .