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Tech
 Notes
 技術專文





 Figure 16. White powder like rust on the robot  Figure 17. SEM images of nanoparticles













                                                    25.3 nm







 Minienvironment enclosure is   The wafer substrate was finally   these nanoparticles are defects in
                    Acc.V  Spot  Magn  WD               1 μm
 used to offer class 1 production   sent to take AFM measuring the   spherical shape. For which is likely   10.0 kV  3.0   80000x   4.5
 environment. HEPA filtration   particles on the surface. The result   to be referred to as the chemical
 module provides particle free   of the AFM survey found that the   reaction product, rather than the
 vertical laminar airflow. But particle   particles were disk like in shape.   debris of irregular appearance.   Figure 18. AFM images of nanoparticles

 pollution is still a problem occurring   The heights were less than 2nm   Furthermore, nanoparticles should
 in the isolated booth. For many   and the diameters were ranging   be highly suspected of the acid-base   Z [μm]
 reasons one could believe that the   from 20nm to 80nm. The AFM   neutralization product, that’s why   1.5  References
 particle is formed from the inside   image is shown in Figure 18. The ion   the reduction of humidity in the   [1]  Michael Lercel,Solving the
 of minienvironment enclosure. To   chromatography sampling exhibited   cleanroom ambient will result in the   nanodefectivity problem,
 address this problem, a combination   high chloride ion and ammonium ion   yield enhancement. The existence   1.0  SEMATECH,November 2012
 of particle active sampling of aerosol   concentration in the samples taken.   of water film on the surface will   [2]  Larry W. Shive, Richard Blank and
                                                                                  Karen Lamb,Investigating the Formation
 condensation particle counter and   The AMC concentration inside the   contribute to the formation of   of Time-Dependent Haze onStored
                      0.5                                                         Wafers,Micro Magazine,2001
 passive sampling of wafer substrate   mini-environment was an incredible   positive and negative ions. Ions are   [3] M .   Odelius, M. Bernasconi, M.
 was performed. Ion chromatography   amount higher than the cleanroom   highly reactive causing corrosion   Parrinello,Two Dimensional Ice
 sampling was utilized to measure   environment.  and oxidation reactions. The idea   Width 47.1nm  Adsorbed on Mica Surface,Physical
                      0.0                     Height 1.82nm                       Review Letters,78,2855,1997.
 AMC concentration in the booth.  behind the survey of nanoparticle            [4]  Lei Xu, Anna Lio, Jun Hu, D. Frank
 defects offers a brand new way   Y [μm]                                          Ogletree, and MiquelSalmeron,Wetting
 Wh ite p owd e r l i ke r ust wa s   to recognize a novel cleanroom              and Capillary Phenomena of Water on
                      -0.5                                                        Mica,The Journal of Physical Chemistry
 observed at the surface of robot and   Result and   design for the next generation of   B, 1998, 102, 540-548
 hatch, which is shown in Figure 16.  semiconductor fabrication.               [5]  Peigen Cao, KeXu,Joseph O. Varghese,
 discussion           -1.0               Width 35.3nm                             and James R. Heath,The Microscopic
                                                                                  Structure of Adsorbed Water on
 Active sampling of the aerosol          Height 1.48nm                            HydrophobicSurfaces under Ambient
 condensation particle counter                                                    Conditions,Nano Letters,2011
                                                                               [6] U .   B altenspergera. Real-time
 accumulated the counts of particles   This article summarizes recent   -1.5      characterization of ultrafine and
 which were larger than 10nm, the   efforts to explore the benefits of   -1.5  -1.0  -0.5  0  0.5  1.0  1.5  accumulation mode particles in ambient
                                              X [μm]                              combustion aerosols.Journal of aerosol
 measuring log showed extremely   low humidity in FOUP purging                    science 33 (2002) 1139–1154.
 low particle concentration in the   systems. Former studies revealed          [7]  Shou-Nan Li1, Hui-Ya Shih, Shaw-Yi
 minienvironment enclosure. Passive   the impact of the existing humidity         Yen, Jean Yang, Case Study of Micro-
 sampling of the wafer substrate   in the semiconductor manufacturing             Contamination Control,Aerosol and
                                                                                  Air Quality Research, Vol. 7, No. 3, pp.
 were sent to take scanning electron   factory and described the effi ciency       432-442, 2007.
 microscopy (SEM) images, resulted   i mprove me nt i n suppre ssi n g         [8]  YitingKuo, Howard Tsao, TuungLuoh,
                                                                                  Ling-WuYang, Tahone Yang, Kuang-
 blurred image of particle clusters,   the defect for mation. Severa l            Chao Chen, andChih-Yuan Lu, "FOUP
 the SEM image is shown in Figure   measurements were performed                   Environment Control andCondense
                                                                                  Reduction", e-Manufacturing &
 17. The nanoparticles were found on   involving Ion chromatography,              DesignCollaboration Symposium 2012.
 the wafer substrate forming vague   aerosol particle counter, SEM and         [9]  Tzu-Sou Chuang, Luh-Maan Chang,
                                                                                  To Mitigate Airborne Molecular
 images due to the shallow depth   AFM. The results show that the
                                                                                  Contamination through Ultra-pure Air
 of field. For the resolution limit of   particle defects are formed from the     System, Building and Environment, Vol.
 Z axis is about 10nm in scanning   inside of mini environment rather             59, January 2013, pp.153-163.
 electron microscopy apparatus.  than the outside air. ITRS assumed


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