Study of AsH3 Plasma Immersion Ion Implantation using PULSION®

Plasma immersion ion implantation (PIII) technology is known as an alternative to overcome the limitations of conventional beam line ion implantation for shallow, high dose and 3D doping on advanced memory and logic devices. This technique also shows a better CoO as the result of higher productivity, smaller footprint and lower operating costs. Implementation in production for P-type doping and development of N-type applications address issues from the challenges linked to the use of hydrides, especially in the case of AsH3 and PH3. Problems of excessive deposition lead to difficult process integration and possible safety issues such as wafer out-gassing. [1]. Higher priced gases coupled with higher gas consumption compared to beam line are often mentioned as limitations. In this paper we present a full characterization (done at Micron and at IBS) of AsH3 plasma implantation using PULSION
^®
(PIII tool produced by IBS). Due to its unique remote source design, PULSION
^®
allows a wider process window using lower gas flows [2]. These design advantages minimize the before mentioned drawbacks allowing easier process integration [3]. AES (Auger Electron Spectroscopy), ARXPS (Angle Resolution X-ray Photoelectron Spectroscopy), TOF-SIMS & D-SIMS (Secondary Ion Mass Spectrometry), and TEM (Transmission Electron Microscopy) analysis are used to study deposition, doping profiles, and amorphization as a function of acceleration voltage and dose. The effect of dose on sheet resistance after Spike anneal is discussed, as well as the effect of possible hydrogen dilution. Out-gassing measurements are also presented.