A method for manufacturing semiconductor absolute pressure sensor units includes anodically bonding a silicon sensor wafer (10) and a silicon cap wafer (12) with a borosilicate glass layer (32) disposed therebetween so as to surround respective sensor chips on the silicon sensor wafer (10) by introducing a matrix shaped conductive layer (28) in contact with and in alignment with the borosilicate glass layer (32), the matrix shaped conductive layer (28) is used as a negative electrode during anodic bonding operation so that a high bonding strength is obtained and sodium ions contained in the borosilicate glass layer (32) are kept away from bond regions after completing the anodically bonding operation.