FRONTSIDE MICROMACHINING USING POROUS-SILICON SACRIFICIAL-LAYER TECHNOLOGIES

Several electro-and photo-electrochemical processes are pointed out wh ich allow silicon microstruc tures to be formed within ion-implanted s ilicon wafers. It is shown how different lateral and vertical doping p rofiles can be used to anodize selectively parts of the ion-implanted silicon wafers, creating isolated regions of porous silicon. After rem oval of the porous silicon in diluted KOH, micromachined structures em erge at the front surface of the silicon wafers which entirely consist of low-stress bulk crystalline silicon.