Single-chip mechatronic microsystem for surface imaging and force response studies.
We report on a stand-alone single-chip (7 x 10 mm) atomic force microscopy unit including a fully integrated array of cantilevers, each of which has an individual actuation, detection, and control unit so that standard atomic force microscopy operations can be performed by means of the chip only without any external controller. The system offers drastically reduced overall size and costs as well as increased scanning speed and can be fabricated with standard complementary metal oxide semiconductor technology with some subsequent micromachining steps to form the cantilevers. Full integration of microelectronic and micromechanical components on the same chip allows for the controlling and monitoring of all system functions. The on-chip circuitry, which includes analog signal amplification and filtering stages with offset compensation, analog-to-digital converters, a powerful digital signal processor, and an on-chip digital interface for data transmission, notably improves the overall system performance. The microsystem characterization evidenced a vertical resolution of < 1 nm and a force resolution of < 1 nN as shown in the measurement results. The monolithic system represents a paradigm of a mechatronic microsystem that allows for precise and fully controlled mechanical manipulation in the nanoworld.