Wafer-scale production of carbon nanofiber probes.

The 4 in. wafer-scale production of probes tipped with single carbon nanofibers (CNF probes) for scanning probe microscope was achieved by an Ar⁺-ion-irradiation method. For the wafer-scale production, an arrangement of commercial-type Si cantilevers (tetrahedral Si tips), onto which single CNFs are grown, was optimized to contain 288 cantilevers in a 4 in. wafer. The ion-induced CNFs were then batch grown in the wafer scale. Scanning electron microscope observation of 50 of 288 probes randomly selected revealed that the CNFs were linear shaped, ∼400 nm in average length and ∼9 nm in average radius, and that ∼80% of the probes batch grown were suitable for practical use as qualified probes. Atomic force microscope image of a densely distributed plastic nanocolumn array obtained by the batch-grown CNF probe was clearer and less distorted, compared to that attained by a conventional Si probe. Thus, the ion-irradiation method opened up new route for the wafer-scale production of CNF probes for practical daily use. [ABSTRACT FROM AUTHOR]