Method of making silicon-on-porous-silicon by ion implantation

A method of producing substantially single crystal silicon-on-porous-silicon comprising the steps off

• (i) manufacturing a porous silicon region on a silicon wafer, such that the silicon wafer has a porous silicon surface and a non-porous silicon surface;
• (ii) applying an implantation dose of greater than 1.times.10.sup.14 ions/cm.sup.2 in two successive ion implantations, with a first ion implantation by F.sup.+ ions followed by a second ion implantation by a species of ion selected from the group consisting of Ge.sup.+, Si.sup.+ and Sn.sup.+, to at least a portion of the porous silicon surface to form a layer of amorphous silicon on a remaining region of porous silicon;
• and
• (iii) recrystallizing the amorphous silicon by annealing at a temperature greater than 350.degree. C. to form a substantially single crystal layer of silicon on the remaining region of porous silicon.

A method of producing substantially single crystal silicon-on-porous-silicon comprising the steps of:

• (i) manufacturing a porous silicon region on a silicon wafer, such that the silicon wafer has a porous silicon surface and a non-porous silicon surface;
• (ii) applying an implantation ion dose of greater than 1.times.10.sup.14 ions/cm.sup.2 in two successive ion implantations, with a first ion implantation by a species of ion selected from the group consisting of Ge.sup.+, Si.sup.+ and Sn.sup.+ followed by a second ion implantation by F.sup.+ ions, to at least a portion of the porous silicon surface to form a layer of amorphous silicon on a remaining region of porous silicon;
• and
• (iii) recrystallizing the amorphous silicon by annealing at a temperature greater than 350.degree. C. to form a substantially single crystal layer of silicon on the remaining region of porous silicon.