Ti/TiN Barrier Improvement for VLSI Metallization

1995 ◽  
Vol 410 ◽  
Author(s):  
Chun-Cho Chen ◽  
Jay L. C. Chao ◽  
K. C. Wang ◽  
Eric Chiang ◽  
J. J. Hsu

ABSTRACTIn this study deposition temperature and post-deposition treatments, such as vacuum break, furnace anneal and RTA, were coupled together to improve Ti/TiN barrier properties. Raising substrate temperature during deposition resulted in lower sheet resistance and stresses, but worse Sheet resistance (Rs) uniformity, suggesting larger-grain growth and non-uniform silicidation. The RTA treatment appeared to be the most effective one to improve barrier integrity due to high temperature densification and oxygen rich along grain boundaries. To include contact geometry effect, the barrier processes were incorporated with hot Al on the contact level of 0.6µm SRAM. After alloying at 430°C for 45 min, the yields turned out to be similar, although the RTA treatment resulted in lower P+ contact resistance, implying more complete activation, silicidation and less dopant segregation. The result suggests that it is feasible to deposit Ti/TiN insitu with hot Al process to enhance throughput. The yield result after a second alloying set at 500°C for 30 min showed that RTA treated Ti/TiN was the only one to survive.

2000 ◽  
Vol 648 ◽  
Author(s):  
Chen Zhang ◽  
Ralph H. Zee ◽  
Paul E. Thoma

AbstractThe microstructure evolution of Ti-rich NiTi thin films and (TiHf)-rich NiTiHf thin films containing 9at% Hf was investigated. These films were deposited from single NiTi and NiTiHf targets using a DC magnetron sputtering system. Free-standing films were obtained by using single crystal silicon substrates. The thickness of these films was controlled between 10-12 μm. In this investigation, the effects of deposition temperature on the surface and cross-sectional microstructures of these films were studied. Substrate temperature during deposition was varied between 300°C to 700°C at 100°C intervals. The influence of post deposition heat treatment (HT) temperature on the microstructure of these films was also studied. The post deposition HT temperature was varied between 300°C and 800°C at 100°C intervals. Both surface and cross- sectional microstructures were examined using a scanning electron microscope (SEM). The crystallinity and the phases present were determined using x-ray diffractometry. All the as- deposited films were found to be crystalline, even when the substrate temperature was as low as 300°C. Results from the microstructure analysis show that all the films have a relatively fine grain size ranging from 0.2 μm to 2.5 μm, and the grain size increases with increasing substrate deposition temperature. The effect of post deposition HT on grain size was found to be minimal.


2013 ◽  
Vol 662 ◽  
pp. 413-416
Author(s):  
Yi Shen ◽  
Ruo He Yao

Al films were prepared by DC magnetron sputter deposition at different substrate temperatures. The sheet resistance of the films was measured by four point probe sheet resistance meter, and the film thickness, which was obtained by surface profiling system. The surface and cross-section morphology of the films was observed by AFM and FESEM. As a result, the resistivity of the films decreases obviously as the substrate temperature increases gradually. The higher substrate temperature is, the rougher the films surface is and the larger the grain size is.


1992 ◽  
Vol 260 ◽  
Author(s):  
A. G. Dirks ◽  
R. A. M. Wolters ◽  
A. E. M. De Veirman

ABSTRACTTungsten-rich W-Ti (or W-Ti-N) alloy films are known for their applicability as diffusion barriers in advanced silicon technology, especially in the case of aluminium-based metallizations. For a wide variety of deposition conditions and post-deposition anneal treatments these refractory-metal barriers show a columnar microstructure. In contact with aluminium the W-Ti films do not form absolute barriers, because of mutual diffusion resulting in compound formation. The reactivity of the W-Ti barriers with the Al99Si1 interconnect has been studied by in-situ resistance measurements in vacuum at temperatures of approximately 450 °C (for W-Ti alloy films) and 475 °C (for W-Ti-N alloy films). In this paper new results dealing with the relationship between deposition conditions, microstructure and barrier properties will be discussed. Furthermore, it will be shown that the actual distribution of the titanium atoms in the tungsten matrix has a substantial influence on the reactivity of the barrier film with the Al99Si1 interconnect.


MRS Advances ◽  
2018 ◽  
Vol 3 (57-58) ◽  
pp. 3397-3402 ◽  
Author(s):  
L.K. Nanver ◽  
K. Lyon ◽  
X. Liu ◽  
J. Italiano ◽  
J. Huffman

ABSTRACTThe chemical-vapor deposition conditions for the growth of pure boron (PureB) layers on silicon at temperatures as low as 400°C were investigated with the purpose of optimizing photodiodes fabricated with PureB anodes for minimal B-layer thickness, low dark current and chemical robustness. The B-deposition is performed in a commercially-available Si epitaxial reactor from a diborane precursor. In-situ methods commonly used to improve the cleanliness of the Si surface before deposition are tested for a deposition temperature of 450°C and PureB layer thickness of 3 nm. Specifically, high-temperature baking in hydrogen, and exposure to HCl are tested. Both material analysis and electrical diode characterization indicate that these extra cleaning steps degrade the properties of the PureB layer and the fabricated diodes.


Author(s):  
А.Я. Виноградов ◽  
С.А. Грудинкин ◽  
Н.А. Беседина ◽  
С.В. Коняхин ◽  
М.К. Рабчинский ◽  
...  

AbstractThe structural, electrical, and optical properties of thin graphite-like films produced by magnetron- assisted sputtering onto crystalline silicon and quartz at substrate temperatures in the range from 320 to 620°C are studied. From analysis of the Raman spectra, it is established that, as the substrate temperature is elevated, the crystallite size increases and the concentration of structural defects and the content of amorphous carbon in the phase composition of the films decrease. It is found that, as the substrate temperature is elevated, the maximum of the absorption intensity in the ultraviolet spectral region of the optical absorption spectra shifts to longer wavelengths and the absorption intensity in the visible and near-infrared spectral regions increases. As the deposition temperature is elevated, the conductivity of the films increases from 0.2 Ω^–1 cm^–1 at 320°C to 30 Ω^–1 cm^–1 at 620°C.


2017 ◽  
Vol 897 ◽  
pp. 87-90 ◽  
Author(s):  
Taguhi Yeghoyan ◽  
Kassem Alassaad ◽  
Véronique Soulière ◽  
Gabriel Ferro

Silicon deposition on 3C-SiC seeds was studied as a function of seed orientations and thicknesses. The 3C-SiC seeds were grown on silicon substrates of (100), (110), (111) and (211) orientations by standard two-step CVD (low temperature carbonization followed by high temperature epitaxy). Then, the Si layers were grown onto these SiC seeds at various temperatures. Almost all the conditions gave polycrystalline deposit. At high deposition temperature (1350°C) the Si deposit was composed of separated hillocks and was never fully covering the 3C-SiC seeds. Lower deposition temperatures (≤ 1100°C) allowed obtaining silicon full coverage but not full epitaxy. Focusing on (100) orientation, it was shown that (100) Si deposit could be obtained but only on the as carbonized 3C-SiC sample, i.e. with the thinner SiC layer.


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