Microporous crystalline silicon of increased band-gap for semiconductor applications

Claim 1

Microporous crystalline silicon for use in active semiconductor applications, wherein said microporous crystalline silicon is produced on a surface of normal semiconducting non-degenerated p-type crystalline silicon, said microporous crystalline silicon consisting essentially of an interconnected bulk-like quantum wire structure, said bulk-like quantum wire having a side length, and said interconnected bulk-like quantum wire structure having an increased band-gap being produced through a process of chemical attack, said chemical attack being carried out on a non-degenerated p-type silicon substrate, said non-degenerated p-type silicon substrate having a resistivity between 0.1 and 30,000 ohm-centimeters and said chemical attack being carried out under an anodic bias such that said chemical attack is limited by charge supply from the semiconducting non-degenerated p-type crystalline silicon, wherein said chemical attack becomes self-limiting as said attack proceeds due to an increase in the band-gap of said interconnected bulk-like quantum wire structure which occurs as said side length decreases to less than 100 Angstroms wherein said chemical attack which is carried out under an anodic bias is carried out in an electrolyte that contains a concentration of hydrofluoric acid wherein said anodic bias is produced by an applied current density whose numerical value, when measured in milliamperes per square centimeter is such that this current density is less than three times the numerical value of said concentration of hydrofluoric acid present in said electrolyte when said concentration is measured in weight percent.