Pressure sensor

A pressure sensor manufactured from a BESOI wafer having first and second silicon layers and an oxide layer arranged therebetween, wherein the pressure sensor comprises:

• an active layer formed from the first silicon layer of the BESOI wafer;
• piezoresistive elements doped in said active layer;
• and
• a membrane carrier formed from the second silicon layer of the BESOI wafer, wherein:
• said membrane carrier externally surrounds a cavity in the second silicon layer, via which a membrane forming region of said active layer and an oxide layer associated therewith are exposed;
• and
• in an outer edge of the region of the oxide layer exposed by said cavity, a groove is provided surrounding the region.

A method for manufacture of a pressure sensor from a BESOI wafer having first and second silicon layers and an oxide layer arranged therebetween, comprising the steps of:

• forming an active layer from the first silicon layer, into which piezoresistive elements are doped;
• forming a membrane carrier from the second silicon layer is formed;
• externally surrounds a cavity in the second silicon layer, via which a membrane forming region of the active layer and an oxide layer associated therewith are exposed, wherein the cavity is formed by removing silicon present in the region of the cavity by means of an etching method, wherein the oxide layer serves as etch stop;
• and,
• etching a groove in an outer edge of the region of the oxide layer exposed by the cavity, by means of an isotropic etching method, the groove surrounding the region.