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1Dp230 at 5:1 dilution in TAE with 12.5mM MgCl2 - on either mica or SiOn as shown below -apply 5ul 1dp230 10nM 1:5 dilution in TAE-Mg (final 2nM) to SiOn surface - used 50V as shown -get no load error while pipette tip with wire is in air -lower and dwell electrode tip loaded with TAE-Mg in drop of non-dia 1D p230 with buffer for 5 seconds -got consistent 25-40uAmp currents -drop blown off, blew in direction of green arrow while current still flowing -followed by rinse with water all rinses are blown along green arrow - rinses remove visible patina completely -mica application is traditional -5 mins, 2x30ul rinse and blow with inert gas -reanneal images involves same electrophoretically prepared SiOn surface rinsed, blown, imaged, rewetted with TAE-MgCl for 10 minutes, rerinsed and wicked dry (no blow) used standard 10ul pipette tip loaded with tae-mg buffer + - W wire Si wafer - piranah - ethanol - acetone cleaned steel disk with conductive tape to back of Si ammeter Si Properties (from ted pella web site): Orientation: <111> Resistance: 1-30 Ohms (resistivity?) Type: P (Boron) (1 primary flat) No SiO2 top coating Wafer thickness: 18-21 mil (460- 530µm) Wafer is polished on one side Before dicing they are rinsed in de-ionized water for cleaning
