Multi-Layer Microactuators For Hard Disk Drive Suspensions

A multi-layer microactuation assembly, comprising:

• a piezoelectric (“PZT”) layer;
• a constraining layer;
• a lower electrode layer on a bottom surface of the PZT layer, the lower electrode layer including:
• a first lower electrode island;
• and
• a second lower electrode island including a main body portion and a finger, the finger extending from the main body portion towards a first end of the multi-layer microactuation assembly;
• a middle electrode layer disposed between a top surface of the PZT layer and a bottom surface of the constraining layer;
• an upper electrode layer on a top surface of the constraining layer;
• a first side end electrode coupled to the upper electrode and extending in a direction substantially orthogonal to the upper electrode towards the lower electrode layer;
• and
• a second side end electrode coupled to the first lower electrode island and extending in a direction substantially orthogonal to the first lower electrode island towards the upper electrode layer, the second side end electrode is configured to electrically connect the first lower electrode island and the middle electrode layer.

A suspension for a hard disk drive comprising:

• a load beam including a dimple;
• a flexure coupled to the load beam and including a spring metal layer, an insulating layer, and a conductive layer, the spring metal layer including a slider mounting region, a first mounting region, and a second mounting region, the slider mounting region having a load point location for engaging the dimple of the load beam, the conductive layer including a power trace and a ground pad, the motor power trace including a terminal pad;
• a first microactuator including:
• a piezoelectric (“PZT”) layer;
• a constraining layer;
• a lower electrode layer on a bottom surface of the PZT layer, the lower electrode layer including:
• a first lower electrode island that is electrically connected to the ground pad;
• and
• a second lower electrode island that is electrically connected to the terminal pad;
• a middle electrode layer disposed between a top surface of the PZT layer and a bottom surface of the constraining layer;
• an upper electrode layer on a top surface of the constraining layer;
• a first side end electrode coupled to the upper electrode and extending in a direction substantially orthogonal to the upper electrode towards the lower electrode layer, the first side end electrode is electrically connected to the terminal pad via a first volume conductive adhesive;
• and
• a second side end electrode coupled to the first lower electrode island and extending in a direction substantially orthogonal to the first lower electrode island towards the upper electrode layer.