This disclosure enables high-productivity fabrication of porous semiconductor layers (made of single layer or multi-layer porous semiconductors such as porous silicon, comprising single porosity or multi-porosity layers). Some applications include fabrication of MEMS separation and sacrificial layers for die detachment and MEMS device fabrication, membrane formation and shallow trench isolation (STI) porous silicon (using porous silicon formation with an optimal porosity and its subsequent oxidation). Further, this disclosure is applicable to the general fields of photovoltaics, MEMS, including sensors and actuators, stand-alone, or integrated with integrated semiconductor microelectronics, semiconductor microelectronics chips and optoelectronics.

This disclosure enables high-productivity fabrication of porous semiconductor layers (made of single layer or multi-layer porous semiconductors such as porous silicon, comprising single porosity or multi-porosity layers). Some applications include fabrication of MEMS separation and sacrificial layers for die detachment and MEMS device fabrication, membrane formation and shallow trench isolation (STI) porous silicon (using porous silicon formation with an optimal porosity and its subsequent oxidation). Further, this disclosure is applicable to the general fields of photovoltaics, MEMS, including sensors and actuators, stand-alone, or integrated with integrated semiconductor microelectronics, semiconductor microelectronics chips and optoelectronics.

This disclosure enables high-productivity fabrication of porous semiconductor layers (made of single layer or multi-layer porous semiconductors such as porous silicon, comprising single porosity or multi-porosity layers). Some applications include fabrication of MEMS separation and sacrificial layers for die detachment and MEMS device fabrication, membrane formation and shallow trench isolation (STI) porous silicon (using porous silicon formation with an optimal porosity and its subsequent oxidation). Further, this disclosure is applicable to the general fields of photovoltaics, MEMS, including sensors and actuators, stand-alone, or integrated with integrated semiconductor microelectronics, semiconductor microelectronics chips and optoelectronics.

This disclosure enables high-productivity fabrication of porous semiconductor layers (made of single layer or multi-layer porous semiconductors such as porous silicon, comprising single porosity or multi-porosity layers). Some applications include fabrication of MEMS separation and sacrificial layers for die detachment and MEMS device fabrication, membrane formation and shallow trench isolation (STI) porous silicon (using porous silicon formation with an optimal porosity and its subsequent oxidation). Further, this disclosure is applicable to the general fields of photovoltaics, MEMS, including sensors and actuators, stand-alone, or integrated with integrated semiconductor microelectronics, semiconductor microelectronics chips and optoelectronics.

A system for recycling machined metal produced by an electrochemical material removal process. The system includes a machining unit and an electrowinning unit. The machining unit includes an anode to receive a workpiece, a cathode tool, and a first pulse generator to provide a voltage or current waveform between the anode and the cathode tool. The electrowinning unit includes an electrowinning cathode, an electrowinning anode, and a second pulse generator to provide a voltage or current waveform between the electrowinning anode and the electrowinning cathode. The machining unit is in fluid communication with the electrowinning unit.

A system for recycling machined metal produced by an electrochemical material removal process. The system includes a machining unit and an electrowinning unit. The machining unit includes an anode to receive a workpiece, a cathode tool, and a first pulse generator to provide a voltage or current waveform between the anode and the cathode tool. The electrowinning unit includes an electrowinning cathode, an electrowinning anode, and a second pulse generator to provide a voltage or current waveform between the electrowinning anode and the electrowinning cathode. The machining unit is in fluid communication with the electrowinning unit.

Anode foil, preferably aluminum anode foil, is etched using a process of treating the foil in an electrolyte bath composition comprising a persulfate, a halide, an oxidizing agent, and a sulfate. An etch resist can be added to the anode foil prior to etching. The anode foil and the attached etch resist can be heated prior to immersing both in an electrolyte bath composition. The anode foil is etched in the electrolyte bath composition by passing a charge through the bath, while maintaining a constant level of persulfate. The etched anode foil is suitable for use in an electrolytic capacitor.

Anode foil, preferably aluminum anode foil, is etched using a process of treating the foil in an electrolyte bath composition comprising a persulfate, a halide, an oxidizing agent, and a sulfate. An etch resist can be added to the anode foil prior to etching. The anode foil and the attached etch resist can be heated prior to immersing both in an electrolyte bath composition. The anode foil is etched in the electrolyte bath composition by passing a charge through the bath, while maintaining a constant level of persulfate. The etched anode foil is suitable for use in an electrolytic capacitor.

A method for recycling metallic material produced by an electrochemical material removal process. The method includes flowing an electrolyte solution between an anode workpiece and a cathode tool in a first electrolytic process, the first electrolytic process including applying a first electrolytic current and voltage between the anode workpiece and the cathode tool and thereby causing metal ions to be removed from the anode workpiece and dissolved and substantially retained in the electrolyte solution. The electrolyte solution with the metal ions therein is passed between an electrowinning cathode and an electrowinning anode in a second electrolytic process, the second electrolytic process including applying a second electrolytic current and voltage between the electrowinning cathode and the electrowinning anode and thereby causing the metal ions to be removed from the electrolyte solution and deposited onto the electrowinning cathode.

A method for recycling metallic material produced by an electrochemical material removal process. The method includes flowing an electrolyte solution between an anode workpiece and a cathode tool in a first electrolytic process, the first electrolytic process including applying a first electrolytic current and voltage between the anode workpiece and the cathode tool and thereby causing metal ions to be removed from the anode workpiece and dissolved and substantially retained in the electrolyte solution. The electrolyte solution with the metal ions therein is passed between an electrowinning cathode and an electrowinning anode in a second electrolytic process, the second electrolytic process including applying a second electrolytic current and voltage between the electrowinning cathode and the electrowinning anode and thereby causing the metal ions to be removed from the electrolyte solution and deposited onto the electrowinning cathode.