Embodiments of systems and methods of etching material from the surface of a wafer are provided. In one representative embodiment, an apparatus comprises a fluid reservoir configured to receive a fluid including an etchant and one or more wafers in a cassette. The apparatus can further comprise a roller member in the fluid reservoir to frictionally engage the one or more wafers and to displace the one or more wafers with respect to a bottom portion of the cassette when the cassette is in the fluid reservoir. The apparatus can further comprise a motor outside the fluid reservoir and magnetically coupled to the roller member such that activation of the motor causes corresponding rotation of the roller member, and thereby rotation of the one or more wafers when the roller member is in frictional engagement with the one or more wafers.