scholarly journals Simulation Of Ultra Shallow Junction Formation For Nano Devices Applications By Dopant Diffusion From Spin On Glasses

2012 ◽  
Author(s):  
Nik Hazura N. Hamat ◽  
Uda Hashim ◽  
Ibrahim Ahmad
Keyword(s):  
Sheet Resistance ◽  
High Performance ◽  
High Surface ◽  
Deep Submicron ◽  
Short Channel ◽  
Shallow Junction ◽  
Si Substrates ◽  
Junction Formation ◽  
Shallow Junctions ◽  
Ultra Shallow Junctions

Bagi merealisasikan MOSFET submikron, simpangan cetek ultra berkerintangan rendah diperlukan bagi menghalang kesan saluran pendek dan bagi meningkatkan peranti. Dalam kajian ini, pembentukan simpangan cetek ultra disimulasikan menggunakan perisian ATHENA dan Silvaco Inc. bagi memodelkan resapan dari SOD ke dalam silikon. Simpangan ultra P+N berkualiti tinggi dengan kedalaman 40 nm telah dibentuk menggunakan ciri–ciri yang baik dengan arus bocor serendah 0.5 na/cm2. Simpangan cetek kurang daripada turut diperoleh tetapi kualiti simpangan–simpangan cetek ini kurang baik disebabkan oleh arus bocor permukaan yang tinggi. Pembentukan simpangan dari resapan lapisan polisilikon di atas silikon diikuti oleh SOD di atasnya menghasilkan simpangan yang lebih cetek yang berkerintangan rendah. Kata kunci: Simpangan cetek ultra, resapan, SOD, ATHENA, MOSFET For realizing deep submicron MOSFETs, ultra shallow junctions with low sheet resistance and high doping concentrations are required to suppress short channel effects and to increase the performance. In this paper, ultra shallow junctions were simulated using ATHENA software package from Silvaco TCAD Tools to model the diffusion from spin on dopant (SOD) into silicon. High performance 40 nm P+N shallow junction fabricated by rapid thermal diffusion of B150 into silicon have been obtained. The junction showed very good characteristics with leakage currents as low as 0.5 nA/cm2. Shallow junctions less than 20 nm have also been obtained but the quality was not very good due to very high surface leakage current. Junction formation by diffusion of polysilicon layer on Si substrates then SOD layer deposition on top of it produced shallower junctions with low sheet resistance. Key words: Ultra shallow junction, MOSFET, ULSI, diffusion, spin on dopant, ATHENA, ATLAS

Ultra-Shallow Junction Formation by a Non-Melting Process; Double-Pulsed Green Laser Annealing

2005 ◽  
Vol 862 ◽  
Author(s):  
Toshio Kudo ◽  
Susumu Sakuragi ◽  
Kazunori Yamazaki
Keyword(s):  
Penetration Depth ◽  
Laser Annealing ◽  
Melting Process ◽  
Green Laser ◽  
Deep Penetration ◽  
Shallow Junction ◽  
Junction Formation ◽  
Ultra Shallow Junctions ◽  
Short Annealing ◽  
Overlap Ratio

AbstractIn order to investigate the possibility of nanosecond activation in the non-melting state, we adopted the method of double-pulsed green laser annealing (DPSS), controlling effectively the combined pulse width with two pulsed lasers (pulse duration: ˜100ns, frequency: 1kHz). We investigated the formation of ultra-shallow junctions (USJ) less than 10nm in spite of the deep penetration depth of the green wavelength in crystalline Si (˜1000nm). In order to limit the depth of B implant, a Ge pre-amorphization implant was performed at an energy of 3keV to a dose of 3E+14/cm2. After the pre-amorphization implant, a B implant was performed at 0.2kev and doses of 5E+14/cm2 and 1E+15/cm2. The implanted B dopants remain within the pre-amorphized Si layer. The double-pulsed laser irradiation was performed with a homogenized line beam of 0.1mm x 17mm, scanning a sample stage at a constant velocity of 10mm/s, that is, at an overlap ratio of 90%. The non-melting state was found to be in the pulse energy density range of E ≤ 780mJ/cm2 at a delay time of 300ns. Overcoming the issues of the short annealing time (˜<1μs) and the deep penetration depth (˜1000nm), we succeeded in the ultra-shallow junction formation beyond the 45nm CMOS node: maximum junction depth of 6nm, minimum sheet resistance of 0.65kohm/sq at a B dose of 1E+15/cm2, an abruptness of 1.4nm/dec.

Influence of amorphization depth on sheet resistance in shallow junction formation with B cluster implantation

2009 ◽  
Author(s):  
Yoji Kawasaki ◽  
Yoshiki Maruyama ◽  
Hidefumi Yoshimura ◽  
Hiroshi Miyatake ◽  
Kentaro Shibahara
Keyword(s):  
Sheet Resistance ◽  
Shallow Junction ◽  
Junction Formation

Integration of NiSi SALICIDE for Deep Submicron CMOS Technologies

1998 ◽  
Vol 514 ◽  
Author(s):  
X. W. Lin ◽  
N. Ibrahim ◽  
L. Topete ◽  
D. Pramanik
Keyword(s):  
Thin Films ◽  
Single Crystal ◽  
Sheet Resistance ◽  
Thermal Annealing ◽  
Cmos Technology ◽  
Deep Submicron ◽  
Thermal Budget ◽  
Si Substrates ◽  
Low Thermal Budget ◽  
Lower Resistivity

ABSTRACTA NiSi-based self-aligned silicidation (SALICIDE) process has been integrated into a 0.25 Ion CMOS technology. It involves rapid thermal annealing (RTA) of Ni thin films (300, Å thick) on Si substrates in the temperature range ≈400 - 700 °C. It was found that the NiSi sheet resistance (Rs) gradually decreases with decreasing linewidth. Parameters, such as RTA temperature, substrate dopant (As vs BF2) and structure (single crystal vs poly), were found to have little effects on Rs. NiSi forms a smoother interface with single crystalSi than with poly Si, and has a slightly lower resistivity. MOSFETs based on NiSi show comparable device characteristics to those obtained with Ti SALICIDE. Upon thermal annealing, NiSi remains stable at 450 °C for more than 39 hours. The same is true for 500 °C anneals up to 6 hours, except for NiSi narrow lines (<0.5 μm) on n+ poly Si substrates whose Rs is moderately increased after a 6 hr anneal. This work demonstrates that with an appropriate low-thermal budget backend process, NiSi SALICIDE can be a viable process for deep submicron ULSI technologies.

I: Ultra-Shallow Junction Cleaning: Metrology for Evaluating Dopant Loss and Substrate Erosion

2007 ◽  
Vol 134 ◽  
pp. 129-131 ◽  
Author(s):  
Mike S. Ameen ◽  
Aseem K. Srivastava ◽  
Ivan L. Berry
Keyword(s):  
Chemical Processes ◽  
Near Surface ◽  
Shallow Junction ◽  
Highly Sensitive ◽  
Shallow Junctions ◽  
Wet Chemical ◽  
The Creation ◽  
Ultra Shallow Junctions ◽  
Dopant Loss ◽  
Surface Proximity

We have investigated the use of Rs and SIMS measurements to quantify substrate erosion due to plasma ashing and subsequent wet cleaning in the creation of ultra-shallow junctions. The near-surface proximity of the implants makes them highly sensitive to various plasma and wet chemical processes. We also observed a dependency on the implant species, dose and energy that can be correlated to substrate damage incurred during implant.

Vacancy Enhanced Boron Activation during Room Temperature Implantation and Low Temperature Annealing

2000 ◽  
Vol 610 ◽  
Author(s):  
Jian-Yue Jina ◽  
Irene Rusakova ◽  
Qinmian Li ◽  
Jiarui Liu ◽  
Wei-Kan Chu
Keyword(s):  
Low Temperature ◽  
Sheet Resistance ◽  
Room Temperature ◽  
Activation Barrier ◽  
Promising Method ◽  
Activation Mechanism ◽  
Rich Region ◽  
Shallow Junction ◽  
Low Temperature Annealing ◽  
Junction Formation

AbstractLow temperature annealing combined with pre-damage (or preamorphization) implantation is a very promising method to overcome the activation barrier in ultra-shallow junction formation. We have made a 32 nm p+/n junction with sheet resistance of 290 /sq. using 20 keV 4×1014 Ω/cm2 Si followed by 2 keV 1×1015 at./cm2 B implantation and 10 minutes 550 °C annealing. This paper studies the boron activation mechanism during low temperature annealing. The result shows that placing B profile in the vacancyrich region has much better boron activation than placing B profile in interstitial-rich region or without pre-damage. It also shows that a significant portion of boron is in substitutional positions before annealing. The amount of substitutional boron is correlated to the amount of vacancies (damage) by the pre-damage Si implantation. The result supports our speculation that vacancy enhances boron activation.

Rapid Thermal Process Requirements for The Annealing of Ultra-Shallow Junctions

1997 ◽  
Vol 470 ◽  
Author(s):  
Daniel F. Downey ◽  
Sonu L. Daryanani ◽  
Marylou Meloni ◽  
Kristen M. Brown ◽  
Susan B. Felch ◽  
...  
Keyword(s):  
Sheet Resistance ◽  
Diffusion Mechanism ◽  
Complex Surface ◽  
Junction Depth ◽  
Enhanced Diffusion ◽  
Shallow Junctions ◽  
Diffusion Mechanisms ◽  
Ultra Shallow Junctions ◽  
Dopant Loss ◽  
Loss Mechanisms

ABSTRACT2. 0 keV 11B+, 2.2 keV 49BF2+ ion implanted and 1.0 kV Plasma Doped (PLAD) wafers of a dose of 1E15/cm2 were annealed at various times and temperatures in a variety of ambiente: 600 to 50,000 ppm O2 in N2; 5% NH3 in N2; N2O; N2 or Ar, in order to investigate the effects of the annealing ambient on the formation of ultra-shallow junctions. RGA data was collected during some (if the anneals to assist in identifying the complex surface chemistry responsible for boron out-diffusion. Subsequent to the anneals, ellipsometric, XPS, four-point probe sheet resistance and SJJVIS measurements were performed to further elucidate the effects of the different ambients on the r etained boron dose, the sheet resistance value, the RTP grown oxide layer and the junction depth. In the cases where oxygen was present, e.g. N2O and O2 in N2, an oxidation enhanced diffusion of the boron was observed. This was most dramatic for the N2O anneals, which at 1050°C 10s diffused the boron an additional 283 to 427 Å, depending on the particular doping condition and species. For the case of BF2 implants and PLAD, anneals in 5% NH3 in N2 reduced the junction depth by a nitridation reduced diffusion mechanism. RGA data indicated that the out-diffusion mechanisms for B and BF2 implanted wafers are different, with the BF2 exhibiting dopant loss mechanisms during the 950°C anneals, producing F containing compounds. B implants did not show doping loss mechanisms, ais observed by the RGA, until the 1050°C anneals and these signals did not contain F containing compounds. Equivalent effective energy boron implants of 8.9 keV BF2 vs. 2.0 keV B, however, indicated that the overall effect of the F in the BF2 implants is very beneficial in the creation of ultra-shallow junctions (compared to B implants): reducing the junction depth by 428 Å, and increasing the electrical activation (determined by SRP) by 11.7%, even though the retained dose (resulting from an increased out-diffusion of B), was decreased by 5.4%.

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