In this thesis an attempt is made to make a step forward in the development of next a generation scanning electron lithography machine for sub 25nm chip making. One of the challenges for such a system is to have sufficient beam-lets with enough current for parallel writing which requires a sufficiently bright electron source. Since the present day commercial electron source is unable to provide the necessary number of beamlets with enough current, an array of bright and stable electron sources such as Schottky emitters is needed. As the Schottky emitter is operated at 1800K, this results in challenges pertaining to alignment between various electrodes and emitters, which is important for beam to beam uniformity and beam stability. This thesis focuses mainly on the study of creating an array of Schottky emitters and addresses the various requirements and issues associated with the design such as thermal loading, positional stability and manufacturability. For parallel electron beam lithography, an array of miniaturized Schottky emitters is proposed. The design of this miniaturized Schottky emitter unit is analyzed thermally in chapter 2 to determine the optimum power and the filament dimensions. A numerical thermal analysis in steady state condition has been done and the temperature of the tip has been determined for different currents and heating filament dimensions. The optimized solution from the model is used for the fabrication of a miniature Schottky emitter. Apart from the heat radiation from the tip, emission from 200 such emitters would generate the considerable thermal load of 200W on the extractor. Chapter 3 describes a possible way of reducing the thermal load on the extractor: it is shown by simulation that the extractor can be operated and the heat load can be halved if the Schottky emitter is operated without suppressor electrode. Simulation results show that if the suppressor electrode is removed, the same field as for the standard configuration can be obtained at the tip apex at an extraction voltage of 2265V instead of 5000V. The estimated total emission without the suppressor electrode rises to 668?A in comparison to 500?A in the standard configuration. However the total heating power dissipating on the extractor would be 40% lower than the standard configuration. The position of the Schottky emitter tip is not stable during its life time. The position stability of the Schottky emitter is an issue as any misalignment with respect to the extractor would result in a change of the virtual source position. An attempt to study the tip stability and its mechanism from a thermo-mechanical point of view is presented in chapter 4. It is concluded that the tip movement is determined by many factors such as thermal history/thermal cycle, stress present and non-symmetrical filament length. Because of a time dependent- stress relaxing creep, the drift rate goes down with time, therefore it is imperative to know the thermal history of the tip to predict its movement. A better creep resistant material such as W-Re alloy for the filament could minimize the effect of creep. However the best alternative is to have a design which can compensate for such drifts. To compensate for the drift in z direction, a possible actuating mechanism was proposed using RTV 566. Chapter 5 reports the preliminary feasibility study of the RTV 566 for its application as a "spring" for in-situ height adjustment in our proposed design for an array of Schottky emitters. Although RTV 566 shows very little hysteresis, it shows clear sign of viscoelastic behavior, rendering it unsuitable for the application. The effort for z actuating of individual tips is then discontinued for the future design process. Another challenge is to miniaturize the Schottky emitter to 1mm diameter. The diameter of a conventional Schottky emitter unit is too large (17.5mm) to use in an array of emitters, which would consist of 200 emitters at a pitch of 1.5 mm. Chapter 6 discusses a novel method of fabricating a miniaturized Schottky emitter of 1mm diameter by Wire-Electro Discharge Machining (WEDM) of polycrystalline tungsten with very good dimensional control and reproducibility. Joule heating in vacuum shows good operational feasibility and temperature stability. Therefore this concept has been considered for the design of Schottky emitter array. Chapter 7 documents various concepts of the Schottky emitter array. This chapter also shows the feasibility based on the results from earlier chapters. After careful evaluation some of the requirements were modified and re-assessed. It is deduced that the design with position control and temperature control would be difficult to implement. A design with no individual temperature and position control is proposed which consists of a tungsten block with monocrystalline tips on it. This, however, would require a large piece of W(100) which is not easily available. Chapter 8 presents the concept of DC Joule heating for the crystallographic transformation to convert polycrystalline tungsten to W(100) for the fabrication of the Schottky emitters. A miniature Schottky emitter fabricated by Wire Electrical Discharge Machining (WEDM) was heated by a DC current and the crystallographic orientation was subsequently determined by electron diffraction. In chapter 9 the design concept was extended for the fabrication of a prototype multi-tip for parallel electron beam lithography using WEDM technique. An attempt is made to recrystallize the tips but the experiment could not be completed. The recrystallization of polycrystalline tungsten in DC Joule heating can open up possibilities of using it in other shape and sizes. However, all the above concepts possess challenges of ensuring a uniform tip radius, where the recipe may need tailoring. A concept of parallel etching is proposed. Combining the above knowledge, a design for a next generation Schottky emitter array is proposed in chapter 10. It consists of four basic units: a heating plate, emitter block consisting of 200 tips, electrodes system and several accessories. The important components included in this design are a simple heater which can be fixed to the emitter block, a water channel in the insulating periphery of the electrodes for the cooling of the electrodes, a piezo-electric stage and an alignment screw plate for the alignment of tips and electrodes. Since the alignment between the tips and electrodes is very critical, it is important to estimate the performance and reliability of such units. In chapter 11, a detailed analysis involving determination of temperature profiles across various electrodes and the resulting stress is carried out by two methods and for two different configurations. The thermal load is evaluated and the necessary cooling is calculated. It is concluded that the thermal load is within the limit if sufficient cooling is done. Although the calculated temperature on the electrodes would not be an issue, the displacement in x-y direction on the extractor/micro-lens could be an issue for the configuration with 4kV extraction and lens voltage. For optimum a design lower voltage on the extractor and the microlens with fixed edges is proposed. Based on the above thermal evaluation, chapter 12 reports the simulation study of the change in the field at the tip apex and the shift in the position of the virtual source of the Schottky emitter for a given shift in the extractor plate by CPO 3D ray tracing calculations. The effect of the lateral and axial shift of the extractor on the field at the tip is negligible. However, the shift in virtual source position in x,y and z direction could be an issue even for a micron displacement. Separate deflectors for each beamlet can be used to compensate the x, y displacement. The axial displacement can be compensated by the piezo-stage with relative ease. The above shift in the virtual source position reduces considerably for the suppressor-less configuration. When the extractor is operated at 1kV, without suppressor, the shift is within the design constraint. Therefore a design without suppressor electrode and an extractor with 1kV potential is the most preferred concept.