JPS5624934A - Manufacture of semiconductor element - Google Patents

Abstract

PURPOSE:To reduce the irregularity of the thickness of the semiconductor element and to shorten the processing time of the element by irradiating and scanning focused laser light onto the surface of a semiconductor substrate when polishing the surface of the substrate. CONSTITUTION:It is necessary to polish the back surface of the semiconductor substrate to obtain preferable electric contact between a package substrate and the semiconductor substrate at the time of die bonding, and is executed by the following method. That is, the surface to be polished of the semiconductor substrate is directed downwardly at the center on the back surface of a substrate fixing stage 4, the semiconductor substrate 3 to be polished is attracted by vacuum chucking means or the like, and the stage 4 is placed at the peripheral edge on a dust collecting machine 5 having an opening at the center. Thereafter, laser light 1a is irradiated from a laser oscillator 1 disposed at the down side of the stage 4 through a reflecting mirror and a focusing lens 2 to the substrate 3 to be scanned in one direction as designated by a scanning line 7, and semiconductor chips thus produced are directed toward duct collecting direction to be collected in the machine 5. In this manner the back surface of the substrate 3 may be cut without irregularity to be adapted for the diaphragm of a pressure sensor.