Semiconductor wafer edge marking

Abstract

The marking of identification and orientation information along the edge (E) of a semiconductor wafer (20, 20′) is disclosed. The information may be marked by way of laser marking at one or more locations (10) along a flat portion (14) or bevel (12t, 12b) of the edge (E) of the wafer (20, 20′). The wafer marking (10) may be encoded, for example by way of a 2-D bar code. A system (30) for reading the identification information from wafers (20, 20′) in a carrier (32) is also disclosed. The system (30) includes a sensor (36) for sensing reflected light from the wafer markings (10) along the wafer edge (E), and for decoding identification and orientation therefrom. A motor (38), under the control of feedback (RFB) from the sensor (36), rotates the wafers (20, 20′) by way of a roller (39) until the wafer marking (10) is in view by the sensor (36). A processing system (40), which includes a rotatable chuck (41) upon which the wafer (20, 20′) is placed, is also disclosed. The processing system (40) also includes a sensor (36) for sensing identification and orientation information from the wafer edge (E), and a process control computer (46) that receives signals corresponding to the identification information, for purposes of manufacturing data logging and process control.

Dependencies are inferred from the claim text.