Diffusion and recrystallization of B implanted in crystalline and pre-amorphized Ge in the presence of F
- Department of Electrical and Computer Engineering and Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758 (United States)
- Department of Physics and Astronomy, The University of Texas at San Antonio, San Antonio, Texas 78249 (United States)
- Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712 (United States)
Although the diffusion control and dopant activation of Ge p-type junctions are straightforward when using B{sup +} implantation, the use of the heavier BF{sub 2}{sup +} ions or even BF{sup +} is still favored in terms of shallow junction formation and throughput—because implants can be done at higher energies, which can give higher beam currents and beam stability—and thus the understanding of the effect of F co-doping becomes important. In this work, we have investigated diffusion and end-of-range (EOR) defect formation for B{sup +}, BF{sup +}, and BF{sub 2}{sup +} implants in crystalline and pre-amorphized Ge, employing rapid thermal annealing at 600 °C and 800 °C for 10 s. It is demonstrated that the diffusion of B is strongly influenced by the temperature, the presence of F, and the depth of amorphous/crystalline interface. The B and F diffusion profiles suggest the formation of B–F complexes and enhanced diffusion by interaction with point defects. In addition, the strong chemical effect of F is found only for B in Ge, while such an effect is vanishingly small for samples implanted with F alone, or co-implanted with P and F, as evidenced by the high residual F concentration in the B-doped samples after annealing. After 600 °C annealing for 10 s, interstitial-induced compressive strain was still observed in the EOR region for the sample implanted with BF{sup +}, as measured by X-ray diffraction. Further analysis by cross-sectional transmission electron microscopy showed that the {311} interstitial clusters are the majority type of EOR defects. The impact of these {311} defects on the electrical performance of Ge p{sup +}/n junctions formed by BF{sup +} implantation was evaluated.
- OSTI ID:
- 22597894
- Journal Information:
- Journal of Applied Physics, Vol. 120, Issue 1; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Implantation induced extended defects and transient enhanced diffusion in silicon
Characterization of ultra shallow p sup + -n junctions formed by a modified low-energy ion implanter and rapid thermal annealing
Related Subjects
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMORPHOUS STATE
ANNEALING
BEAM CURRENTS
BORON FLUORIDES
BORON IONS
CONCENTRATION RATIO
DEFECTS
DIFFUSION
DOPED MATERIALS
GERMANIUM
PHOSPHORUS IONS
P-N JUNCTIONS
POINT DEFECTS
P-TYPE CONDUCTORS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION