Zhimin Wan

Process Characterization Of Low Temperature Ion Implantation Using Ribbon Beam And Spot Beam On The AIBT iPulsar High Current

The damage and amorphous layer formation properties of a 6 keV 1×1015 cm−2 carbon implant were investigated using spot beam and ribbon beam and substrate temperature. The effects of wafer temperature on dopant activation and diffusion were further investigated for boron implants between 300 eV and 2 keV and arsenic implants between 2 keV and 20 keV. The carbon implant amorphization characteristics can be understood using the concept of critical dose for amorphization. B and As activation was found to be 15%–20% improved at the lowest implant temperature but with similar junction depths compared to higher implant temperatures. Higher energy implants showed less or no activation or junction depth improvement at lower implant temperatures.

Characterization of an RF plasma ion source for ion implantation

A novel inductively coupled RF plasma ion source has been developed for use in a beamline ion implanter. Ion density data have been taken with an array of four Langmuir probes spaced equally at the source extraction arc slit. These provide ion density uniformity information as a function of source pressure, RF power and gas mixture composition. In addition, total extracted ion beam current data are presented for the same conditions. The comparative advantages of the RF source in terms of higher beam current, reduced maintenance and overall productivity improvement compared to a hot cathode source are discussed.

Ribbon and Spot Beam Process Performance of the Dual Mode iPulsar High Current Ion Implanter

Low energy implant process data are presented from a dual mode high current ion implanter. The iPulsar is a flexible single wafer implanter capable of running both ribbon beams with one‐dimensional mechanical scan of the wafer and spot beams with two‐dimensional wafer scan. The main components of the implanter are described and their operation explained. Boron concentration profiles in Ge pre‐amorphized substrates, measured by secondary ion mass spectroscopy (SIMS) are presented before and after anneal with drift and decelerated beams. In addition, spot and ribbon beam as‐implanted phosphorus and carbon profiles are presented and the characteristics of each mode of operation are discussed.