Silicides for 65 nm CMOS and Beyond

AbstractAn overview of silicide development for the 65 nm node and beyond is presented. The scaling behavior of Co based and Ni based silicides to sub-100 nm junctions and sub-40 nm gate lengths was investigated. Co and Co-Ni silicides required a high thermal budget to achieve low diode leakage. Even for lower thermal budgets, the sheet resistance of Co and Co-Ni silicides increased at gate lengths below 40 nm. NiSi had low sheet resistance down to 30 nm gate lengths exhibiting a reverse linewidth effect (sheet resistance decreased with decreasing linewidth), achieved lower contact resistivity than CoSi2 and lower diode leakage for similar sheet resistance values. Bridging issues cannot be ignored for NiSi, in particular for thicker Ni films, higher RTP temperatures and in the presence of Ti. Material issues for the application of NiSi were also investigated. Ni2Si was found to grow with diffusion limited kinetics in the 225-300°C range, with an activation energy of 1.5 eV. Results of the kinetic studies were used to design a two-step RTP process that limited the silicide thickness on small features by a low thermal budget first RTP step, reducing the reverse linewidth effect and avoiding excessive silicidation. In the presence of an interfacial oxide, undesired epitaxial NiSi2 pyramidal grains grew directly at temperatures as low as 310°C on p+ Si. Thermal stability of NiSi was also investigated. We found that the initial mechanism of degradation for thin NiSi films was agglomeration, with activation energies of 2.5-3 eV. The surface after agglomeration remained quite flat with alternating NiSi and exposed Si areas, while the interface roughened significantly. Thick films also degraded initially by agglomeration at low temperatures, but by transformation to NiSi2 at higher temperatures. The addition of Pt improved thermal stability of NiSi films against agglomeration. The Ni/Si-Ge reaction was also studied, finding that the addition of Ge reduced the thermal process window and resulted in a slightly higher resistivity.

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Electronic Properties and Thermal Stability of Defects Induced by MeV Electron/Ion Irradiations in Unstrained Germanium and SiGe Alloys

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.108-109.253 ◽

2005 ◽

Vol 108-109 ◽

pp. 253-260 ◽

Cited By ~ 6

Author(s):

Vladimir P. Markevich ◽

Anthony R. Peaker ◽

L.I. Murin ◽

Valentin V. Emtsev ◽

Valentin V. Litvinov ◽

...

Keyword(s):

Thermal Stability ◽

Irradiation Damage ◽

Γ Irradiation ◽

Thermal Budget ◽

Enhanced Diffusion ◽

Vacancy Clusters ◽

Implantation Damage ◽

Defect Reactions ◽

Low Thermal Budget ◽

Thermal Stability Of

Deep states produced during γ irradiation of germanium have been compared with the defects produced by 1 and 3MeV silicon ion implantation. The deep states have been studied using DLTS and Laplace DLTS techniques. Isochronal annealing has been used to investigate the defect evolution and stability over the range 100 to 500°C. It is found that while irradiation damage can be removed with a very low thermal budget, the implantation damage is more complex and much more difficult to remove. By comparing low (1010cm-2) and high (1012cm-2) implantation doses it appears that both the complexity and stability of defects increases with increasing dose. Similar experiments have been performed on Ge rich Si1-xGex (x=0.992). The focus of this work has been on vacancy related defects. It is believed that the diffusion of both acceptors and donors is vacancy mediated in Ge and so vacancy clusters rather than interstitial clusters are expected to be the technologically significant defect in enhanced diffusion. The significance in terms of junction leakage and generation currents are discussed in the paper in the context of the observed defect reactions.

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Curing Process Window and Thermal Stability of Porous MSQ-Based Low-Dielectric-Constant Materials

Journal of The Electrochemical Society ◽

10.1149/1.1731520 ◽

2004 ◽

Vol 151 (6) ◽

pp. F146 ◽

Cited By ~ 14

Author(s):

Shou-Yi Chang ◽

Tzu-Jen Chou ◽

Yung-Cheng Lu ◽

Syun-Ming Jang ◽

Su-Jien Lin ◽

...

Keyword(s):

Thermal Stability ◽

Dielectric Constant ◽

Low Dielectric Constant ◽

Process Window ◽

Curing Process ◽

Low Dielectric ◽

Low Dielectric Constant Materials ◽

Thermal Stability Of

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Integration of NiSi SALICIDE for Deep Submicron CMOS Technologies

MRS Proceedings ◽

10.1557/proc-514-179 ◽

1998 ◽

Vol 514 ◽

Cited By ~ 8

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.

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Diffusion-Limited Crystallization: A Rationale for the Thermal Stability of Non-Fullerene Solar Cells

ACS Applied Materials & Interfaces ◽

10.1021/acsami.9b04554 ◽

2019 ◽

Vol 11 (24) ◽

pp. 21766-21774 ◽

Cited By ~ 16

Author(s):

Liyang Yu ◽

Deping Qian ◽

Sara Marina ◽

Ferry A. A. Nugroho ◽

Anirudh Sharma ◽

...

Keyword(s):

Thermal Stability ◽

Solar Cells ◽

Diffusion Limited ◽

Thermal Stability Of

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Implant isolation of ZnO epitaxial layers

MRS Proceedings ◽

10.1557/proc-744-m3.5 ◽

2002 ◽

Vol 744 ◽

Author(s):

S. O. Kucheyev ◽

C. Jagadish ◽

J. S. Williams ◽

P. N. K. Deenapanray ◽

Mitsuaki Yano ◽

...

Keyword(s):

Thermal Stability ◽

Single Crystal ◽

Sheet Resistance ◽

Annealing Temperature ◽

Ion Beam ◽

Irradiation Temperature ◽

Minor Effect ◽

Electrical Isolation ◽

Atomic Displacements ◽

Thermal Stability Of

ABSTRACTThe formation of highly resistive films of single-crystal ZnO as a result of irradiation with MeV Li, O, and Si ions is demonstrated. Results show that the ion doses necessary for electrical isolation close-to-inversely depend on the number of ion-beam-generated atomic displacements. Results show that an increase in the dose of 2 MeV O ions (up to ∼ 2 orders of magnitude above the threshold isolation dose) and irradiation temperature (up to 350 °C) has a relatively minor effect on the thermal stability of electrical isolation, which is limited to temperatures of ∼ 300 — 400 °C. For the case of multiple-energy implantation with keV Cr, Fe, or Ni ions, the evolution of sheet resistance with annealing temperature is consistent with defect-induced isolation, with a relatively minor effect of Cr, Fe, or Ni impurities on the thermal stability of isolation. Based on these results, the mechanism for electrical isolation in ZnO by ion bombardment is discussed.

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Aromaticity-Controlled Thermal Stability of Photochromic Systems Based on a Six-Membered Ring as Ethene Bridges: Photochemical and Kinetic Studies

Chemistry - A European Journal ◽

10.1002/chem.201200354 ◽

2012 ◽

Vol 18 (37) ◽

pp. 11685-11694 ◽

Cited By ~ 38

Author(s):

Yuheng Yang ◽

Yongshu Xie ◽

Qiong Zhang ◽

Keitaro Nakatani ◽

He Tian ◽

...

Keyword(s):

Thermal Stability ◽

Kinetic Studies ◽

Membered Ring ◽

Thermal Stability Of

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Propargylic-Terminated Prepolymers. 5. Mechanistic and Kinetic Studies of the Polymerization Reaction of Compounds with an Imide Group meta to the Propargylic Function

High Performance Polymers ◽

10.1088/0954-0083/8/4/006 ◽

1996 ◽

Vol 8 (4) ◽

pp. 555-578 ◽

Cited By ~ 9

Author(s):

Marie–Florence Grenier–Loustalot ◽

Corinne Sanglar

Keyword(s):

Thermal Stability ◽

Reaction Kinetics ◽

Liquid State ◽

Reaction Path ◽

Kinetic Studies ◽

Polymerization Reaction ◽

Imide Group ◽

Final System ◽

Thermal Stability Of

We have synthesized two functionalized prepolymers with an imide group meta to the propargylic function in their central skeleton. Based on data obtained by a variety of solid and liquid state physicochemical techniques, we show that meta substitution modifies the reaction path and leads to the formation of two chromenes, α and β. In addition, the reaction kinetics and thermal stability of the final system are affected by the presence of an imide group in the structure of the propargylic prepolymer.

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Thermal Stability of Platinum Silicide in Deep Sub-Micron Lines

MRS Proceedings ◽

10.1557/proc-391-223 ◽

1995 ◽

Vol 391 ◽

Cited By ~ 4

Author(s):

Dan-Xia Xu ◽

Suhit R. Das ◽

Lynden Erickson ◽

Abdalla Naem

Keyword(s):

Thermal Stability ◽

Sheet Resistance ◽

Annealing Temperature ◽

Electrical Conductance ◽

Sharp Decrease ◽

Platinum Silicide ◽

Deflection System ◽

Stability Of Resistance ◽

Pt Films ◽

Thermal Stability Of

AbstractThe properties of platinum silicide have been evaluated in the form of blanket films and confined lines with linewidth down to 0.15 μm. Pt films, ranging in thickness from 150Å to 1000Å, were prepared by sputter-deposition onto Si (100) blanket substrates or substrates patterned with windows of various sizes in SiO2. The samples were then annealed in a rapid thermal annealing system up to 550°C to form PtSi. The sheet resistance of silicide lines did not change significantly with linewidth. The thermal stability of the sheet resistance of PtSi was also measured for different linewidths and film thicknesses. The sheet resistance remained stable on annealing up to 850°C for a silicide film made of 250Å Pt and did not appear to be sensitive to the linewidth. The thickness dependence of the thermal stability of resistance was also evaluated.The stress of the silicide films was measured using a laser deflection system. The asdeposited metal films were under compressive stress, but the stress turned into tensile upon annealing when silicide started to form. After PtSi was formed, the stress remained stable with annealing temperature until approximately 900°C when the stress exhibited a sharp decrease. Unlike electrical conductance, however, the breakdown temperature for stress did not strongly depend on the film thickness.

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