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Carbon nanotubes were fabricated close together so that their separation is smaller than their height and field enhancement effects at the apexes of the tubes are diminished due to electrostatic shielding. Bundling was achieved by embedding the tubes into a PCVD silicon dioxide, followed by HF etching, water rinsing, and nitrogen drying. Emission measurements were performed in a vacuum system at a pressure of 4 × 10-9 Torr. Current-voltage characteristics were obtained at room temperature, 120 °C and 170 °C. Macroscopic current densities of 20 mA/cm2 were obtained with a 0.5 mm diameter tungsten anode. The turn-on fields are about 15 V/μm.