Surface Oxidation Effects During Low Energy BF{sub 2}{sup +} Ion Implantation

Journal Article · Fri Jan 07 00:00:00 EST 2011 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3548327· OSTI ID:21510091

Kondratenko, Serguei ^[1]; Hsu, P K; Zhao, Hongchen ^[2]; Reece, Ronald N

---

1. Axcelis Technologies, 108 Cherry Hill Drive, Beverly, MA 01915 (United States)
2. Axcelis Technologies, 19F Kirin Plaza, 666 Gubei Road, Shanghai, China 200336 (China)

We present results on silicon wafer surface oxidation observed during low energy high dose BF{sub 2}{sup +} implantation. Experiments were performed on single-crystal and pre-amorphized silicon wafers that help elucidate the surface structure impact on boron distribution profiles and dose retention. Implanters with different architectures were compared including both single wafer and batch systems. It was found that the oxidation rate depends on implanter type and design, and that the surface oxide thickness is a linear function of implantation dose and time. Surface oxidation is significantly higher for batch systems compared to single wafer tools. This is due primarily to the significantly lower beam duty cycle on the batch implanter. The oxide thicknesses estimated from SIMS oxygen profiles are in agreement with ellipsometry measurements after spike annealing, and show a similar difference between single wafer and batch implanters. SIMS boron distribution profiles after implantation were compared and used to calculate retained dose. In the medium dose range ({<=}3x10{sup 14} at/cm{sup 2}) the profiles from different implanters are well matched and the dose retention is close to 100%. For the higher dose range ({>=}3x10{sup 15} at/cm{sup 2}) retention for the batch implanter is significantly less than the single wafer tool and depends on the wafer surface structure. A higher oxidation rate results in lower dopant activation and higher Rs value after spike annealing. For high implantation doses the single wafer system allows much higher dose retention and better boron activation after annealing.

• OSTI ID: 21510091
• Journal Information: AIP Conference Proceedings, Vol. 1321, Issue 1; Conference: IIT 2010: 18. international conference on ion implantation technology, Kyoto (Japan), 6-11 Jun 2010; Other Information: DOI: 10.1063/1.3548327; (c) 2010 American Institute of Physics; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
AMORPHOUS STATE
ANNEALING
BEAMS
BORON FLUORIDES
DISTRIBUTION
ELLIPSOMETRY
IMPLANTS
ION IMPLANTATION
ION MICROPROBE ANALYSIS
MASS SPECTROSCOPY
MOLECULAR IONS
MONOCRYSTALS
OXIDATION
OXYGEN
RADIATION DOSES
SILICON
SURFACES
THICKNESS
BORON COMPOUNDS
CHARGED PARTICLES
CHEMICAL ANALYSIS
CHEMICAL REACTIONS
CRYSTALS
DIMENSIONS
DOSES
ELEMENTS
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HEAT TREATMENTS
IONS
MEASURING METHODS
MICROANALYSIS
NONDESTRUCTIVE ANALYSIS
NONMETALS
SEMIMETALS
SPECTROSCOPY