Identification and quantification of FOUP molecular contaminants inducing defects in integrated circuits manufacturing

• Published in: Microelectronic engineering Vol. 105; pp. 124 - 129
• Main Authors: Nguyen, Thi Quynh, Fontaine, Hervé, Borde, Yannick, Jacob, Véronique
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.05.2013; Elsevier
• Subjects: Acetic acid; AMC; Applied sciences; Contaminants; Contamination; Corrosion; Corrosion mechanisms; Cross-contamination; Cross-disciplinary physics: materials science; rheology; Crystal defects; Design. Technologies. Operation analysis. Testing; Dry Stripping; Electronics; Etching; Exact sciences and technology; Formic acid; General (including economical and industrial fields); Implantation; Integrated circuits; Materials science; Metals. Metallurgy; Methods of crystal growth; physics of crystal growth; Patterning; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Semiconductors; Cross-contamination; Formic acid; AMC; Etching; Acetic acid; HF; Dry Stripping; Crystal growth; Doping; Molecular crystals; Integrated circuit manufacture; p type semiconductor; n type semiconductor; Defect; Manufacturing; Copper; Wafer; Patterning; Dry etching; Implantation; Contamination; Corrosion; Electronics industry; Interconnection; Spacer; Integrated circuit
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2012.04.008

In the semiconductor industry, the control of contaminants is mandatory in order to prevent their detrimental impact on manufacturing yield. More specifically, it has been found that molecular contaminants coming from FOUPs could lead to defects on wafer. This paper presents two cases related with defects induced by molecular contamination, namely crystal growth and corrosion issues, respectively along two process sequences: (1) copper interconnect patterning and (2) Ionic Implantation of N-type or P-type dopants before Spacer Deposition. Three main ionic contaminants have been identified: HF, CH3COOH, HCOOH with levels varying from few ppbv to few tens of ppbv. In the first process sequence, dry Etching step has been identified as the source of contamination. In the second process sequence CF4 dry Stripping step generates HF. On the other hand, dry Stripping step and Implantation step generate CH3COOH, HCOOH. Organic contaminants have been characterized showing that the FOUP atmosphere represents a contaminated environment (about few tens of ppbv for total organics). A specific organic composition has been identified for in-process FOUPs but has not been related to a process or defects.