Heterogeneously Integrated Vapor–Liquid–Solid Grown Silicon Probes/(111) and Silicon MOSFETs/(100)

In this letter, we report the heterogeneous integration of vertically aligned silicon (Si) microprobe arrays/(111) with MOSFET circuits/(100) by IC processes and subsequent selective vapor-liquid-solid (VLS) growth of Si. A hybrid Si-on-insulator (SOI) substrate with different species of Si layers, e.g., a (100)-top-Si/buried oxide/(111)-handle-Si system, was utilized for the heterogeneous integration technique. MOSFETs were fabricated on (100) top Si, and vertical VLS probes were synthesized at the selectively exposed (111) handle Si. The different Si layers of the MOSFETs and probes were electrically connected by a 3-D metallization technique. In addition, the electrical properties of 3-D metallization and the MOSFETs were investigated. The results indicate potential for heterogeneous integration of VLS probes/(111) and MOSFETs/(100), promising further integrations of numerous microdevices/different species of substrates and CMOS/(100), including fully depleted SOI-CMOS for high-performance electronics, on the same chip.