A concept for maskless digital electrostatic focused e-beam array direct-write lithography (DEAL) has been developed at Oak Ridge National Laboratory, USA [1]. This concept incorporates a digitally addressable array field emission array (DAFEA) of Vertically Aligned Carbon Nanofibers (VACNF) built along with Dose Control Circuitry (DCC) and Logic Memory Control (LMC) circuits to function as the write head for an e-beam lithography tool. The DCC regulates charge emission from the VACNFs and prevents resists from being over exposed during the e-beam lithography process [2]. This lithography concept can be used to fabricate ultra-small feature size devices, while eliminating the manufacturing costs of photo-masks. Prototypes of the DAFEA have been fabricated and used to test the focusing of the electron beams and to pattern lines in polymethyl methacrylate (PMMA) resist [3]. This paper discusses the complete integration of the prototype DEAL device with the DCC. Previous work in this area has not addressed the issues involving the interface between VACNFs and the control electronics although a detailed discussion of the DCC has been published [2]. The emission of electrons from the VACNF tip requires relatively high voltage. The I-V characteristic of a typical VACNF based device is shown in figure 1. From the figure we see that the threshold voltage of the VACNF is about 75 V. The DCC built using a standard 5V digital CMOS process cannot handle such voltage levels.
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