Surface plasma source to generate high-brightness H− beams for ion projection lithographya)

Abstract

A surface plasma source with Penning-type electrodes is developed to generate H− beams for ion projection lithography applications. The source presently runs in pulsed mode with a pulse width of about 1 ms and repetition rate of 10 Hz. The discharge and the extracted H− beam are maintained in stable, noiseless condition; gas pressure plays a critical role here. The maximum H− beam current density at the emission surface is about 1.7 A/cm2. Preliminary measurements suggest that the normalized brightness of the core beam is ∼1.7×1013 A/(m rad)2 and its perpendicular temperature is about 0.2 eV.

Negative hydrogen ion production mechanisms

“…42 shows how small an SPS is. The figure introduces an SPS of Penning discharge ion source structure, 226 while the original success of high intensity H À ion beam production had been realized with the magnetron discharge geometry. 25 The magnetron SPS utilizes the selfextraction mechanism and many sources have been designed with grooves at the cathode for geometrical focusing of H À ions.…”

High-brightness ion source for ion projection lithography

“…Details of the ion source and its special electronics system have been described elsewhere. 8 The beam characteristics are determined using several diagnostics: ͑i͒ a toroid and a biased plate to measure the beam current, ͑ii͒ a deep Faraday cup to measure the current distribution, ͑iii͒ a pepper-pot system to measure the beam emittance and estimate the perpendicular temperature, and ͑iv͒ a retarding potential analyzer to determine the energy distribution and estimate the energy spread of the beam. This article focuses on the measurement of energy spread, and some details of the energy analyzer are discussed below.…”