Dissertation/ Thesis
Investigation of Metal (Ti, TiN) Chemical Vapor Deposition and Copper Electrodeposition for ULSI Metallization Applications
| العنوان: | Investigation of Metal (Ti, TiN) Chemical Vapor Deposition and Copper Electrodeposition for ULSI Metallization Applications |
|---|---|
| Alternate Title: | 金屬化學氣相沉積技術與電化學方式沈積銅導線在積體電路金屬化製程之應用與研究 |
| المؤلفون: | Jung-Chih Hu, 胡榮治 |
| Thesis Advisors: | Lih-Juann Chen, Ting-Chang Chang, 陳力俊, 張鼎張 |
| سنة النشر: | 2000 |
| المجموعة: | National Digital Library of Theses and Dissertations in Taiwan |
| الوصف: | 88 Metal (Ti, TiN) chemical vapor deposition (CVD) and copper electrodeposition for future ULSI metallization applications have been investigated. For CVD barrier deposition, the conformal TiN films were deposited by thermal low-pressure chemical vapor deposition (LPCVD) in a rotating disk reactor, using TiCl4 and NH3 with N2 as a dilution gas. TiN plug with 0.05 mm contact size was achieved. No void formation was observed in the TiN plug. The result demonstrated that LPCVD-TiN can be used to fill very small contact holes. The excellent step coverage and uniformity are resulted from a surface reaction-rate-limited deposition. The resistivity of TiN film was reduced to 133 mW-cm by in-situ NH3 plasma post-treatment. In addition, the resistivity of multilayered Ti/TiN films grown by chemical vapor deposition can be reduced from 240 mW-cm (standard sample) to 120 mW-cm with NH3 plasma post-treatment for 300 s. Therefore, increasing the number of multilayered of Ti/TiN films and plasma post-treatment technique contributed to the reduction in the resistivity of TiN films effectively. For CVD TiSi2 deposition, a novel PECVD to form TiSi2 in-situ was studied. Pure C-54 TiSi2 with Ar precleaning treatment was found after 650 ℃ RTA for 30 s. However, in the samples without Ar precleaning treatment, the C-54 TiSi2 was not found until the annealing was carried at a temperature higher than 750 ℃ for 30 s. It is thought that Ar plasma soft etching provides clean surface on Si, hence the reaction of CVD Ti with Si to form pure C-54 TiSi2 at low temperature was enhanced by plasma enhanced chemical vapor deposition. For electroplated Cu deposition, the effects of a new combination of additives in electroplating solution on the properties of Cu thin films have been investigated. The electroplated Cu films exhibit an excellent super-filling behavior. Low resistivity, low porosity, and highly uniform electroplated Cu films were obtained. Strong (111) texture was found for the electroplated Cu films. The resistivity of a 600-nm-thick Cu film is 1.80 mW-cm. The leveling behavior of organic additives "L" is proposed to produce a strongly conjugated p-bonding structure in the carboxylic group and aromatic rings. According to diffusion-controlled mechanism of leveling agent, it assumed that organic additives would be consumed at the cathode by electroreduction. Thus, the reduced products of the organic ester compound "L" contained carboxylic acid, aldehyde, alcohol, and even methyl groups. The organic impurities (C, O, S, and N) of electroplated Cu film are rather low compared to IMP-Cu films. From TEM observation, a high density of twins in the electroplated Cu grains was obtained. The tendency for the formation of twins during the growth process is more likely in materials with very low twin-boundary energy compared to the grain-boundary energy. When the current density was increased, rougher Cu films were obtained. The Cu2+ ions can more readily diffuse to kink sites in low current density than that in high current density. Therefore, more uniform Cu films can be achieved by low current density. 0.14 mm trenches with an aspect ratio exceeding 5 were filled completely without any void or seam formation. |
| Original Identifier: | 088NTHU0159106 |
| نوع الوثيقة: | 學位論文 ; thesis |
| وصف الملف: | 154 |
| الاتاحة: | http://ndltd.ncl.edu.tw/handle/07310167978700391886 |
| رقم الانضمام: | edsndl.TW.088NTHU0159106 |
| قاعدة البيانات: | Networked Digital Library of Theses & Dissertations |
| الوصف غير متاح. |