Abstract: A reproducible process for uniformly etching silicon from a series of micromechanical structures used in electrical devices and the like includes providing a micromechanical structure having a silicon layer with defined areas for removal thereon and an electrochemical cell containing an aqueous hydrofluoric acid electrolyte. The micromechanical structure is submerged in the electrochemical cell and the defined areas of the silicon layer thereon are anodically biased by passing a current through the electrochemical cell for a time period sufficient to cause the defined areas of the silicon layer to become porous. The formation of the depth of the porous silicon is regulated by controlling the amount of current passing through the electrochemical cell. The micromechanical structure is then removed from the electrochemical cell and submerged in a hydroxide solution to remove the porous silicon.

Abstract: A plated steel strip having an enhanced corrosion and rust resistance and an improved paint-coating property comprises a principal plating layer formed on a steel strip substrate and comprising a co-deposited zinc-chromium based alloy which comprises more than 5% by weight but not more than 40% by weight of chromium and the balance of zinc.

Abstract: The fabrication of porous cadmium electrodes is disclosed in which high cadmium loading without surface buildup is obtained by using a relatively low current density (approximately 0.2 amperes per square inch of plaque area) and period current reversals of time durations approximately equal to 15% of the forward time durations at a current density substantially equal to the forward current density.