Micromachined barbed spikes for mechanical chip attachment

We investigated the mechanical attachment of chips to surfaces capable of being penetrated by silicon spike,,. The attachment principle is inspired by fishhooks and arrows. Barbed spikes penetrate a material but offer resistance to detaching forces. Two types of barbed spikes were etched in silicon using deep reactive ion etching (DRIE). The mechanical attachment of both types of barbed spike arrays was measured on non-biological materials (polyethylene foil (PE), aluminium foil and Parafilm(TM)) as well as on human skin. The maximum adhesion force was 1.36 N achieved by a 2 x 2 mm(2) chip containing 64 barbed spikes, 160 mum in length, pressed into PE. Maximum adhesion in skin was 0.54 N. The shape of the two different barb types has significant influence on the detachment forces for non-biological materials. (C) 2002 Elsevier Science B.V. All rights reserved.