Focused-ion-beam chemical vapor deposition (FIB-CVD) is an excellent technology for forming three-dimensional nanostructures. Various diamond-like-carbon (DLC) free-space-wirings have been demonstrated by FIB-CVD using a computer-controlled pattern generator, which is a commercially available pattern generator for electron-beam (EB) lithography. The material composition and crystal structure of DLC free-space-wiring were studied by transmission-electron microscopy and energy-dispersive x-ray spectroscopy. As a result, it became clear that DLC free-space-wiring is amorphous carbon containing a Ga core in the wire. Furthermore, the electrical resistivity measurement of DLC free-space-wiring was carried out by two terminal electrodes. Au electrodes were fabricated by EB lithography and a lift-off process. The electrical resistivity was about 100 Ω cm at room temperature.

We used SU-8 shrinkage to fabricate strained graphene resonators to produce a high quality factor in a graphene resonator. A-few-layer graphene resonators were fabricated on a trench of an SU-8 resist. These resonators were clamped with diamond-like carbon (DLC), which was deposited by using focused-ion-beam chemical vapor deposition (FIB-CVD), and trimmed by using FIB etching. Annealing was used to apply tensile strain to the graphene resonators because SU-8 shrinks drastically. We also observed an increase in resonant frequency and quality factor in these graphene resonators after annealing. At room temperature, the quality factor of the best sample exceeded 7,000 for a resonator length of 10 µm.

We studied the fabrication of free-designed three-dimensional (3D) structures by using focused-ion-beam chemical-vapor deposition. The 3D structures are fabricated by scanning 30 keV Ga+ ion-beam-assisted deposition in a 1×10−4 Pa phenanthrene atmosphere. The scanning pattern and blanking signal of the ion beam are generated by a 3D computer-aided-designed model using a computer pattern-generating system. This 3D pattern-generating system is able to fabricate overhang and hollow structures by setting suitable parameters (for example, plot pitch, dwell time, time interval of irradiations, and priorities of scanning). In this article, we demonstrate the performance of a 3D pattern-generating system by fabricating a 1:100 000 000 scale model of the Enterprise spaceship, a microring, a moth’s eyelike structure, and a morpho butterflylike structure with 200 nm spacing.

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