Spatially Controlled Transience Of Graphene-Polymer Electronics With Silicon Singulation

Transient electronics are an emerging technology for civilian and government applications that require controlled disintegration of an electronic chip into smaller components, by physical or chemical means. Here, a pillar-on-polymer architecture is presented for a transient system where the electronic components are partitioned on an array of silicon pillars. The pillars are mechanically tethered by a vaporizable polymer film and electrically routed with atomically thin graphene interconnects. Polymer vaporization is achieved with Joule heating of thin-film metal heaters associated with each silicon pillar, which singulates the pillar. The pillar singulation breaks the graphene interconnects locally, without collateral damage to other on-chip components. This process demonstrates a methodology for temporally and spatially controlled transience as any single pillar can be singulated at any time. A novel polymer-silicon layer transfer fabrication process is used to microfabricate a 3 x 3 array of 200 mu m diameter silicon pillars spaced 200 mu m apart, with gold heaters and graphene interconnects, and the controlled singulation of individual pillars is demonstrated. As a demonstration of a sensor in this technology, a piezoresistive accelerometer is integrated with this platform, which uses a silicon pillar array suspended from the polymer film as a proof mass.