A Comparison of Low Energy BF2 Implantation in Si and Ge Preamorphized Silicon

MRS Proceedings ◽

10.1557/proc-128-611 ◽

1988 ◽

Vol 128 ◽

Cited By ~ 7

Author(s):

Gary A. Ruggles ◽

Shin-Nam Hong ◽

Jimmie J. Wortman ◽

Mehmet Ozturk ◽

Edward R. Myers ◽

...

Keyword(s):

Ion Implantation ◽

Crystalline Silicon ◽

Amorphous Layer ◽

Low Energy ◽

Electrical Activation ◽

Silicon Substrates ◽

Boron Diffusion ◽

Junction Depth ◽

Rapid Thermal Anneal ◽

Boron Segregation

ABSTRACTLow energy (6 keV) BF2 implantation was carried out using single crystal, Ge-preamorphized, and Si-preamorphized silicon substrates. Implanted substrates were rapid thermal annealed at temperatures from 600°C to 1050'C and boron channeling, diffusion, and activation were studied. Ge and Si preamorphization energies were chosen to produce nearly identical amorphous layer depths as determined by TEM micrographs (approximately 40 nm in both cases). Boron segregation to the end-of-range damage region was observed for 6 keV BF2 implantation into crystalline silicon, although none was detected in preamorphized substrates. Junction depths as shallow as 50 nm were obtained. In this ultra-low energy regime for ion implantation, boron diffusion was found to be as important as boron channeling in determining the junction depth, and thus, preamorphization does not result in a significant reduction in junction depth. However, the formation of junctions shallower than 100 rmu appears to require RTA temperatures below 1000°C which can lead to incomplete activation unless the substrate has been preamorphized. In the case of preamorphized samples, Hall measurements revealed that nearly complete electrical activation can be obtained for preamorphized samples after a 10 second rapid thermal anneal at temperatures as low as 600°C.

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Study of BF2 ion implantation into crystalline silicon : Influence of fluorine on boron diffusion

MRS Proceedings ◽

10.1557/proc-810-c8.9 ◽

2004 ◽

Vol 810 ◽

Cited By ~ 1

Author(s):

Lilya Ihaddadene-Lecoq ◽

Jerome Marcon ◽

Kaouther Ketata

Keyword(s):

Mass Spectrometry ◽

Ion Implantation ◽

Secondary Ion Mass Spectrometry ◽

Crystalline Silicon ◽

Low Energy ◽

Concentration Profiles ◽

Boron Diffusion ◽

Boron Difluoride ◽

Secondary Ion ◽

Trap Interstitial

ABSTRACTWe have investigated and modeled the diffusion of boron implanted into crystalline silicon in the form of boron difluoride BF2+. Low energy BF2+ 1×1015 cm−2 implantations at 2.0keV were characterized using Secondary Ion Mass Spectrometry (SIMS) in order to measure dopant profiles. RTA was carried out at 950°C, 1000°C, 1050°C and 1100°C during 10s, 20s, 30s and 60s. The results show that concentration profiles for BF2+ implant are shallower than those for a direct B+ ion implantation. This could be attributed to the presence of fluorine which trap interstitial Si so that interstitial silicon supersaturation is low near the surface.

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TEM Characterization of Arsenic and Phosphorus Implanted Silicon Devices

Microscopy and Microanalysis ◽

10.1017/s1431927600009223 ◽

1997 ◽

Vol 3 (S2) ◽

pp. 467-468

Author(s):

Lancy Tsung ◽

Hun-Lian Tsai ◽

Alwin Tsao ◽

Makoto Takemura

Keyword(s):

Ion Implantation ◽

Crystalline Silicon ◽

Source Region ◽

Amorphous Layer ◽

Common Source ◽

Silicon Devices ◽

Similar Region ◽

Before And After ◽

P Type ◽

Silicon Device

Ion implantation of arsenic and phosphorus is a common practice in silicon devices for the formation of transistor source/drain regions. We used a TEM equipped with EDX capabilities to investigate effects of ion implantation in actual devices before and after annealing. A 200 kev field emission gun TEM was used in this study. Two implant cases were studied here. Both samples are p-type, (100) Si wafers.Figure 1 shows the microstructure in a common source region of a silicon device after being implanted by phosphorus (4x1014 cm−2 at 30 kv, 0°), while Figure 2 shows a similar region for arsenic implantation (5x1015 cm−2 at 45 kv, 0°). No screen layer was used during implantation. The phosphorus implant results in a ˜0.05 μm amorphous layer sandwiched between heavily damaged crystalline silicon. High resolution images reveal a rough amorphous/damaged crystalline boundary and high density defects due to silicon lattice displacements.

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Application of molecular dynamics for low-energy ion implantation in crystalline silicon

Journal of Vacuum Science & Technology B Microelectronics and Nanometer Structures Processing Measurement and Phenomena ◽

10.1116/1.2137333 ◽

2006 ◽

Vol 24 (1) ◽

pp. 462 ◽

Cited By ~ 1

Author(s):

H. Y. Chan ◽

M. P. Srinivasan ◽

N. J. Montgomery ◽

C. P. A. Mulcahy ◽

S. Biswas ◽

...

Keyword(s):

Molecular Dynamics ◽

Ion Implantation ◽

Crystalline Silicon ◽

Low Energy

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Atomic transport properties and electrical activation of ultra-low energy implanted boron in crystalline silicon

Materials Science in Semiconductor Processing ◽

10.1016/s1369-8001(99)00004-9 ◽

1999 ◽

Vol 2 (1) ◽

pp. 35-44 ◽

Cited By ~ 27

Author(s):

V Privitera ◽

E Napolitani ◽

F Priolo ◽

S Moffatt ◽

A La Magna ◽

...

Keyword(s):

Transport Properties ◽

Crystalline Silicon ◽

Low Energy ◽

Electrical Activation ◽

Atomic Transport

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Ultra-Low Energy Boron Implants in Crystalline Silicon: Atomic Transport Properties and Electrical Activation

MRS Proceedings ◽

10.1557/proc-568-43 ◽

1999 ◽

Vol 568 ◽

Cited By ~ 1

Author(s):

E. Napolitani ◽

A. Carnera ◽

V. Privitera ◽

A. La Magna ◽

E. Schroer ◽

...

Keyword(s):

Transport Properties ◽

Point Defects ◽

Crystalline Silicon ◽

Low Energy ◽

Electrical Activation ◽

Epitaxial Silicon ◽

High Concentration ◽

Enhanced Diffusion ◽

Atomic Transport ◽

Wide Range

ABSTRACTWe investigated the atomic transport properties and electrical activation of boron in crystalline epitaxial silicon after ultra-low energy ion implantation (0.25–1 keV) and rapid thermal annealing (750–1100 °C). A wide range of implant doses was investigated (3×1012-1×105/cm2). A fast Transient Enhanced Diffusion (TED) pulse is observed involving the tail of the implanted Boron, the profile displacement being dependent on the implant dose. The excess of interstitials able to promote enhanced diffusion of implanted boron occurs, provided the implant dose is high enough to generate a significant total number of point defects. The Boron diffusion following the fast initial TED pulse can be described by the equilibrium diffusion equations.The electrical activation of ultra-shallow implants is hard to achieve, due to the high concentration of dopant and point defects confined in a very shallow layer that significantly contributes to the formation of clusters and complex defects. Provided a correct combination of annealing temperatures and times for these ultra-shallow implants is chosen, however, a sheet resistance 500 Δ/square with a junction depth below 0.1μm can be obtained, which has a noteworthy technological relevance for the future generations of semiconductor devices.

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Low-energy ion implantation for shallow junction crystalline silicon solar cell

Solar Energy ◽

10.1016/j.solener.2016.01.059 ◽

2016 ◽

Vol 130 ◽

pp. 25-32 ◽

Cited By ~ 7

Author(s):

Wei-Lin Yang ◽

Tai-Ying Lin ◽

Shu-Sheng Lien ◽

Likarn Wang

Keyword(s):

Solar Cell ◽

Ion Implantation ◽

Silicon Solar Cell ◽

Crystalline Silicon ◽

Low Energy ◽

Crystalline Silicon Solar Cell ◽

Shallow Junction

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Cryo-Implantation Technology for Controlling Defects and impurity out diffusion

MRS Proceedings ◽

10.1557/proc-610-b3.8 ◽

2000 ◽

Vol 610 ◽

Cited By ~ 7

Author(s):

Atsushi Murakoshi ◽

Kyoichi Suguro ◽

Masao Iwase ◽

Mitsuhiro Tomita ◽

Katsuya Okumura

Keyword(s):

Ion Implantation ◽

Substrate Temperature ◽

Single Crystal ◽

Room Temperature ◽

Amorphous Layer ◽

Junction Depth ◽

Si Substrate ◽

Enhanced Diffusion ◽

Pn Junction ◽

Order Of Magnitude

AbstractWe propose a novel process module by using cryo-implantation and rapid thermal annealing (RTA). Boron or arsenic ions were implanted into a 8 inch (100) Si substrate which was cooled by using liquid nitrogen. The substrate temperature was controlled to be below at -160°C during ion implantation. It was found that an amorphous layer was formed by boron or arsenic implantation and the amorphous layer was completely recovered to a single crystal after annealing at 900°C for 30sec. No dislocation was observed in the implanted layer. It was also found that the thermal diffusion of boron was suppressed by cryo-implantation. PN junction depth was found to be about 10-20% shallower than that of room temperature implantation. These results suggest that transient enhanced diffusion of boron can be reduced by suppressing vacancy migration toward the surface during implantation. Cryo-implantation was found to be very effective in reducing defects and PN junction leakage was successfully reduced by one order of magnitude as compared with room temperature implantation.

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Damage-to-dose ratio after low energy silicon ion implantation into crystalline silicon

Journal of Materials Research ◽

10.1557/jmr.1993.2305 ◽

1993 ◽

Vol 8 (9) ◽

pp. 2305-2309 ◽

Cited By ~ 1

Author(s):

Y. Levin ◽

N. Herbots ◽

S. Dunham

Keyword(s):

Ion Implantation ◽

Crystalline Silicon ◽

Crystal Surface ◽

Effective Diffusivity ◽

Low Energy ◽

Parallel Computer ◽

Analytic Approximation ◽

Dose Ratio ◽

Experimental Conditions ◽

Diffusion Of Vacancies

In this work, we develop a model describing the diffusion of vacancies and self-interstitials and their recombination during ion implantation. The model includes the effect of the moving surface due to regrowth and the defect generation rate as a function of depth based on Monte Carlo simulations. The results are compared to experimental measurements of the damage-to-dose ratio (DDR) after low energy, 40 eV, silicon ion implantation into silicon at 300 and 685 K. We have derived an analytic approximation which agrees with the results of the computational model, implemented on a CM-2 parallel computer. We find that the calculated effective diffusivity, the main adjustable parameter in the simulations, is much lower than predicted based on extrapolation from experiments at higher temperatures. We attribute this difference to the aggregation of self-interstitials. We also find that the effect of interstitial-vacancy recombination on DDR is negligible under the experimental conditions considered; however, the crystal surface motion has a significant impact on the results.

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