This article describes the extension of atomic force microprobe (AFM) technology to two dimensions (2D) for accurate measurement of submicron critical dimensions (CDs). The system utilizes a vibrating tip with heterodyne-interferometer sensor similar to that introduced by Martin, Williams, and Wickramasinghe. [Y. Martin, C. C. Williams, and H. K. Wickramasinghe, J. Appl. Phys. 61, 4723 (1987)]. However, the tip vibrates in 2D with dual heterodyne detection. The sample is moved relative to the tip by means of coarse- and fine-motion stages whose position is monitored with 3D interferometry. The system does not scan the sample, but operates like a nanorobot sensing the approach of the tip to the surface by means of the vibration damping. A special three-point tip has been fabricated by Lee [K. L. Lee, D. W. Abraham, F. Serord, and L. Landstein, Proceedings of the 35th ISEIPB Conference, Seattle, WA, May 28–31, 1991 (unpublished), paper K1] with 0.1 μm shank diameter which allows measurement of submicrometer trench widths up to 2 μm in depth with accuracy and repeatability at the nanometer level. Measurements are made under computer control. The system design and operating characteristics are discussed.