Method for registering a mask pattern in a photo-etching apparatus for semiconductor devices

Claim 1

A method for registering a pattern on a mask plate with a pattern already formed on a semiconductor wafer; characterized by the steps of forming at a predetermined position on said wafer a reflector group which consists of a plurality of reflectors of predetermined shape aligned at a predetermined pitch along a predetermined direction; forming first and second window groups at predetermined positions on said mask plate in correspondence to the position of said reflector group on the wafer, each window group consisting of a plurality of windows of predetermined shape aligned at the same predetermined pitch along the same direction as the reflector group, one window group being provided with a staggered phase relationship equal to a multiple of one half of said predetermined pitch with respect to the other window group; moving one of said wafer and said mask plate relative to the other in the direction of alignment of the reflectors and windows while irradiating said reflector group with light; providing first and second detecting means for determining the quantity of light reflected by the reflector group and passing through said first and second window groups, respectively; and determining the relative position of the wafer and the mask plate by determining when the detected respective quantities of light take a predetermined proportion to thereby register the pattern on said mask plate with the pattern already formed on said semiconductor wafer.

Claim 2

A method for registering a pattern on a mask plate with a pattern already formed on a semiconductor wafer; characterized by the steps of forming at a predetermined position on said wafer a reflector group which consists of a plurality of reflectors of predetermined shape aligned at a predetermined pitch along a predetermined direction; forming first and second window groups at predetermined positions on said mask plate in correspondence to the position of said reflector group on the wafer, each window group consisting of a plurality of windows of predetermined shape aligned at the same predetermined pitch along the same direction as the reflector group, one window group being provided with a staggered phase relationship equal to a multiple of one half of said predetermined pitch with respect to the other window group; moving one of said wafer and said mask plate relative to the other in the direction of alignment of the reflectors and windows while irradiating said reflector group with light; providing first and second detecting means for determining the quantity of light reflected by the reflector group and passing through said first and second window groups, respectively; and determining the relative position of the wafer and the mask plate by determining when the detected respective quantities of light take a predetermined proportion to thereby register the pattern on said mask plate with the pattern already formed on said semiconductor wafer.

Claim 3

A method for registering a pattern on a mask plate with a pattern already formed on a semiconductor wafer characterized by the steps of forming at a predetermined position on said mask a window group which consists of a plurality of windows of predetermined shape aligned at a predetermined pitch along a predetermined direction; forming first and second reflector groups at predetermined positions on said wafer in correspondence to the position of said window group on the mask plate, each reflector group consisting of a plurality of reflectors of predetermined shape aligned at the same pitch along the same direction as the window group, one reflector group being provided with a staggered phase relationship equal to a multiple of one half of said predetermined pitch with respect to the other reflector group; moving one of said wafer and said mask plate relative to the other in the direction of alignment of the reflectors and windows while irradiating said reflector groups with light; providing first and second detecting means for determining the quantity of light reflected by the first and second reflector groups and passed through the window group, respectively; and determining the relative position of the wafer and the mask plate by determining when the detected respective quantities of light take a predetermined proportion to thereby register the pattern on said mask plate with the pattern already formed on said semiconductor wafer.

Claim 4

A method for registering a pattern on a mask plate with a pattern already formed on a semiconductor wafer characterized by the steps of forming at a predetermined position on said mask a window group which consists of a plurality of windows of predetermined shape aligned at a predetermined pitch along a predetermined direction; forming first and second reflector groups at predetermined positions on said wafer in correspondence to the position of said window group on the mask plate, each reflector group consisting of a plurality of reflectors of predetermined shape aligned at the same pitch along the same direction as the window group, one reflector group being provided with a staggered phase relationship equal to a multiple of one half of said predetermined pitch with respect to the other reflector group; moving one of said wafer and said mask plate relative to the other in the direction of alignment of the reflectors and windows while irradiating said reflector groups with light; providing first and second detecting means for determining the quantity of light reflected by the first and second reflector groups and passed through the window group, respectively; and determining the relative position of the wafer and the mask plate by determining when the detected respective quantities of light take a predetermined proportion to thereby register the pattern on said mask plate with the pattern already formed on said semiconductor wafer.