Breakable tethers for microelectromechanical system devices utilizing reactive ion etching lag

A method of forming a microactuator in a disc drive having a recording disc rotatable about an axis, a slider supporting a transducing head for transducing data with the disc, and an actuation system supporting the slider to position the transducing head adjacent a selected radial track of the disc, the method comprising:

• defining a microactuator device area on a substrate wafer;
• forming a microactuator frame in the microactuator device area, the microactuator frame including a plurality of flexible beam springs operatively attachable to the slider to permit movement of the slider during operation of the microactuator;
• masking the substrate wafer to define a channel around a periphery of the microactuator device area, having a first width along a first portion of the channel and having a second width less than the first width along a second portion of the channel;
• etching the substrate wafer with a reactive ion etching (RIE) process, so that the microactuator frame is separated from the substrate wafer along the first portion of the channel and breakable tethers are formed connecting the microactuator frame to the substrate wafer along the second portion of the channel.