A Qualitative Analysis on the Efficiency of Rca Standard Clean Method Using External Visual Inspection(Evi)
A Qualitative Analysis on the Efficiency of RCA Standard Clean Method using External Visual Inspection(EVI)
|Abarro, Ghizelle Jane E. |
|Department of Mining, Metallurgical and Materials Engineering |
|University of the Philippines, Diliman |
|ghizellejanea@yahoo.com/ghizellejane@gmail.com |
Abstract
The different steps in wafer fabrication such as photolithography, layer deposition and the machines and equipments used cause organic and inorganic particles to settle on the silicon wafer causing various defects in the semiconductor. Such defects can be minimized through wafer cleaning; RCA standard clean is a method generally used for this purpose. This technical report aims to discuss the chemical process of RCA cleaning and provide a qualitative analysis on the cleaning capability of RCA standard clean. The method includes removal of organic contamination with H2O-H2O2-NH4OH solution ( 5:1:1) , removal of hydrous film using H2O-HF solution (50:1) and elimination of metallic contaminants with H2O-H2O2-HCl solution (6:1:1). Three wafers were cleaned with the three-step-method and observed using external visual inspection before and after cleaning. The final results were compared to the appearance of a dummy wafer which was not cleaned. Both organic and inorganic Although the results were precise and in agreement with previous literature writings, certain important properties of the surface were not investigated such as surface roughness, color and the property of substances left on the surface.
Introduction
As early as the 1950s, the importance of clean
|Abarro, Ghizelle Jane E. |
|Department of Mining, Metallurgical and Materials Engineering |
|University of the Philippines, Diliman |
|ghizellejanea@yahoo.com/ghizellejane@gmail.com |
Abstract
The different steps in wafer fabrication such as photolithography, layer deposition and the machines and equipments used cause organic and inorganic particles to settle on the silicon wafer causing various defects in the semiconductor. Such defects can be minimized through wafer cleaning; RCA standard clean is a method generally used for this purpose. This technical report aims to discuss the chemical process of RCA cleaning and provide a qualitative analysis on the cleaning capability of RCA standard clean. The method includes removal of organic contamination with H2O-H2O2-NH4OH solution ( 5:1:1) , removal of hydrous film using H2O-HF solution (50:1) and elimination of metallic contaminants with H2O-H2O2-HCl solution (6:1:1). Three wafers were cleaned with the three-step-method and observed using external visual inspection before and after cleaning. The final results were compared to the appearance of a dummy wafer which was not cleaned. Both organic and inorganic Although the results were precise and in agreement with previous literature writings, certain important properties of the surface were not investigated such as surface roughness, color and the property of substances left on the surface.
Introduction
As early as the 1950s, the importance of clean
References: [1] F. Beck. Integrated Circuit Failure Analysis: A Guide to Preparation Techniques, pp. 52-53, John Wiley and Sons, England, 1998. [2] S. A. Campbell. The Science and Engineering of Microelectronic Fabrication, Chapter 14, Oxford University Press, New York, 1996. [3] B. EL-Kareh. Fundamentals of Semiconductor Processing Technologies, pp. 268-269, Kluwer Academic Publishers Boston, USA, 1995. [4] W. Kern. "The Evolution of Silicon Wafer Cleaning Technology" J. Electrochem. Soc. volume 137 pp.1887-1891 [5] P. Van Zant. Microchip Fabrication: A Practical Guide to Semiconductor Processing 2nd ed., Chapter 7, McGraw Hill Publishing Co. USA, 1976. [6] S. Clark, “The RCA Cleaning Process”, Bold Technologies, Inc., 1998-2000. Accessed 23Jun12 through URL http://www.bold-tech.com/technical/rca_cleaning.html