Technology process. It s very small world. Electronics and Microelectronics AE4B34EM. Why is the integration so beneficial?

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1 It s very small world Electronics and Microelectronics AE4B34EM 9. lecture IC processing technology Wafer fabrication Lithography How to get Components to 1 cm 2 Human hair on the surface of the chip It s very small world Technology process More than transistors in 45nm technology can be integrated on the surface of full stop. From The Oregonian, April 07, 2008 Why is the integration so beneficial? Improve functionality of the system Higher speed an performance Increase whole system reliability Lower power consumption Billions of identical electronic components are assembled on one single chip with 100% functionality Lower Price Basic steps of IC processing Preparation of single crystal Si wafer Lithography Etching Thermal oxidation or deposition of silicon dioxide Diffusion Ion Implantation Physical, chemical deposition Epitaxial growth Packaging and Encapsulating Testing

2 Clean rooms In the normal living environment is about 10 million particles in cubic meter. In such an environment would be impossible to manufacture semiconductor devices Fresh air Exhausted air Some pictures from IC process Special clothing, boots, gloves, masks Selling filters Air velocity 0,5 m/s Overpressure Pa Adjustment Temperature and humidity particles Leakage Perforated floor IC Technology Fab

3 IC processing technology - video Preparation of single crystal Si wafers 23BCE720D421E520&playnext=1&playnext_from=PL&index=30 Single chip Wafer Today, we use wafers up to 15" (45 cm) diameter Wafer evolution 150 mm 200 mm roky Monocrystal growth Edge grinding Grinding and polishing Diameter in mm 300 mm 450 (6358) Monocrystal milling Etching (Surface in cm²) 300 (706,8) (122,5) 150 (176,7) (314,1) Cutting of the ends Polishing 50 (19,6) 75 (44,2) 100 (78,5) Veneers cut Testing Slurry Polishing head Year of invention : 450 mm Intel Samsung TSMC Wafer cutting Polishing table Czochralsky method monocrystal growth Monocrystal holder and a rotary mechanism Silicon melts at 1415 C compared to iron at 1535 C, aluminum at 660 º C. Monocrystal nucleus Monocrystal Melted Si Melting pot Heating Heating Insulating cap

4 Single crystal Growth unit Single crystal processing Wafer Polishing Type conductivity (P or N) and crystallographic orientation of silicon are encoded in the relative position of the main and auxiliary veneers Contaminated ends are cut off The surface of the wafer must be perfectly smoothed without any scratches and bumps. Accuracy is at the nanoscale. Wafer Cutter Diameter adjustment Veneer cutter The upper polishing plate Wafer Abrasive material The lower polishing plate Wafer polishing unit Wafer processing technology - video laylist&p=e513a3c80416fa47&index=0&playnext=1

5 Measurement of wafers characteristics The size and properties of wafers Black points White points Imaging Optics Half mirror Light source Lens Imaging Optics The light reflected by the surface heterogeneity Lens Diameter (mm) Thickness ( m) Surface (cm 2 ) Weight (grams) Why we want bigger diameter? Defects in the IC process 25% 80% 88 chips 200-mm wafer 232 chips 300-mm wafer We expect the size of microprocessors 1,5 x 1,5 cm The yield (number of good wafers) corresponds chip size Chip Price depends on Yield The yield Úlomek křemíku Number _ of _ good _ chips _ on _ wafer Y.100% Number _ of _ all _ chips _ on _ wafer Wafer _ price Chip _ price Number _ of _ good _ chips Y

6 Lithography process How to get the layer topology on the silicon chip Lithography is a technique in which selected portions of given layer can be masked out Types of lithography: Photolithography Electron lithography X-ray lithography Types of lithography It is one of the factors that affect the density of integration Photolithography DUV Photoresist after processing (picture shows a PolySi layer grown on top of SiO 2 ) PolySi layer after etching and removal of photoresist. Electron lithography with direct exposure X-ray photolithography 5 1,0 0,5 0,2 0,1 0,05 0,2 0,01 m Radiation sources in ultraviolet region Photolithography Oxidation Optical mask Ultra violet region Visible region EUV VUV DUV Mid-UV Ultraviolet Blue Green Yellow Orange Red l (nm) i h g Next technology step photoresist removal Photoresist coating Typical operation steps in one photolithographic cycle Washing, drying Exposition Photoresist processing Etching laser Mercury lamp