Parallel inspection of semiconductor wafers by a plurality of different inspection stations to maximize throughput

A system for inspecting semiconductor wafers of at least one lot of semiconductor wafers during integrated circuit fabrication, the system comprising:

• a plurality of different inspection stations, wherein each different inspection station inspects a respective integrated circuit fabrication feature of a semiconductor wafer, and wherein said plurality of inspection stations are for ADI (After Development Inspection) in a photolithography process during fabrication of integrated circuits;
• a semiconductor wafer robotic handling system, operatively coupled to each of said inspection stations, for transferring said semiconductor wafers between said inspection stations;
• and
• a host server, coupled to said inspection stations and said semiconductor wafer robotic handling system;
• wherein said host server controls said semiconductor wafer robotic handling system to transfer a predetermined one of said semiconductor wafers to a predetermined one of said inspection stations at a predetermined time;
• wherein said host server controls each of said inspection stations to simultaneously inspect in parallel a respective one of said semiconductor wafers for said respective integrated circuit fabrication feature;
• wherein each inspection station has a respective set of recipes with each recipe of said set being used for inspecting a respective set of integrated circuit fabrication parameters for a respective lot of semiconductor wafers, and wherein said host server controls each inspection station to use a respective recipe corresponding to a lot of each semiconductor wafer transferred to an inspection station;
• wherein said respective set of recipes for each inspection station is stored at said host server, and wherein each inspection station downloads from said host server a respective recipe, for a semiconductor wafer, corresponding to a lot of semiconductor wafers transferred to an inspection station;
• wherein each inspection station operates in one of interface mode and stand-alone mode, and wherein an inspection station interfaces with said semiconductor wafer robotic handling system and said host server to operate under control of said host server when operating in said interface mode, and wherein an inspection station stops interfacing with said semiconductor wafer robotic handling system and said host server to operate without control by said host server when operating in said stand-alone mode;
• wherein said host server sends a stand-alone indicator signal to each of said inspection stations for controlling said inspection stations to operate in said stand-alone mode when one of said host server and said semiconductor wafer robotic handling system is inoperative;
• wherein each inspection station sends to said host server respective data after inspecting said respective integrated circuit fabrication feature of a semiconductor wafer of a respective lot of semiconductor wafers;
• wherein said host server determines whether said respective data received from each inspection station is within a respective range corresponding to said respective integrated circuit fabrication feature for said inspection station and corresponding to said respective lot of semiconductor wafers;
• wherein said host server controls an inspection station to re-inspect said respective integrated circuit fabrication feature of a semiconductor wafer if said respective data received from said inspection station is not within said respective range;
• and wherein said host server controls each of said inspection stations to terminate inspection of said respective lot of semiconductor wafers if said respective data received from said inspection station for a defective semiconductor wafer of said respective lot of semiconductor wafers is not within said respective range after said inspection station re-inspects said respective integrated circuit fabrication feature of said defective semiconductor wafer.

A method for inspecting semiconductor wafers of at least one lot of semiconductor wafers during integrated circuit fabrication, the method including steps of:

• coupling a host server to a plurality of different inspection stations and to a semiconductor wafer robotic handling system, wherein each different inspection station inspect a respective integrated circuit fabrication feature of a semiconductor wafer, and wherein said semiconductor wafer robotic handling system transfers said semiconductor wafers between said inspection stations;
• controlling said semiconductor wafer robotic handling system, by said host server, to transfer a predetermined one of said semiconductor wafers to a predetermined one of said inspection stations at a predetermined time;
• controlling each of said inspection station, by said host server, to simultaneously inspect in parallel a respective one of said semiconductor wafers for said respective integrated circuit fabrication feature;
• sending, by each inspection station to said host server, respective data after inspecting said respective integrated circuit fabrication feature of a semiconductor wafer of a respective lot of semiconductor wafers;
• determining by said host server whether said respective data received from each inspection station is within a respective range corresponding to said respective integrated circuit fabrication feature for said inspection station and corresponding to said respective lot of semiconductor wafers, to determine whether said semiconductor wafer passes or fails inspection at said inspection station;
• and
• controlling, by said host server, each of said inspection stations to terminate inspection of the lot of semiconductor wafers corresponding to said semiconductor wafer that has failed inspection at said inspection station.

A method for inspecting semiconductor wafers of at least one lot of semiconductor wafers during integrated circuit fabrication, the method including steps of:

• coupling a host server to a plurality of different inspection stations and to a semiconductor wafer robotic handling system, wherein each different inspection station inspects a respective integrated circuit fabrication feature of a semiconductor wafer, and wherein said semiconductor wafer robotic handling system transfers said semiconductor wafers between inspection stations, and wherein said plurality of inspection stations are for ADI (After Development Inspection) is a photolithography process during fabrication of integrated circuits;
• controlling said semiconductor wafer robotic handling system, by said host server, to transfer a predetermined one of said semiconductor wafers to a predetermined one of said inspection stations at a predetermined time;
• controlling each of said inspection stations, by said host server, to simultaneously inspect in parallel a respective one of said semiconductor wafers for said respective integrated circuit fabrication feature;
• wherein each inspection station has a respective set of recipes with each recipe of said set being used for inspecting set of integrated circuit fabrication parameters for a respective lot of semiconductor wafers, and wherein said method further includes the step of:
• controlling each inspection station, by said host server, to use a respective recipe corresponding to a lot of each semiconductor wafer transferred to an inspection station;
• wherein said respective set of recipes for each inspection station is stored at said host server, and wherein said method further includes the step of:
• downloading from said host server, by cash inspection station, a respective recipe, for a semiconductor wafer, corresponding to a lot of semiconductor wafers transferred to an inspection station;
• operating in one of interface mode and stand-alone mode by cash inspection station, wherein an inspection station interfaces with said semiconductor wafer robotic handling system and said host server to operate under control of said host server when operating in said interface mode, and wherein an inspection station stops interfacing with said semiconductor wafer robotic handling system and said host server to operate without control by said host server when operating in said stand-alone mode;
• sending a stand-alone indicator signal, by said host server, to each of said inspection stations for controlling said inspection stations to operate in said stand-alone mode when one of said host server and said semiconductor wafer robotic handling system is inoperative;
• sending, by each inspection station to said host server, respective data after inspecting said respective integrated circuit fabrication feature of a semiconductor wafer of a respective lot of semiconductor wafers;
• determining, by said host server, whether said respective data received from each inspection station is within a respective range corresponding to said respective integrated circuit fabrication feature for said inspection station and corresponding to said respective lot of semiconductor wafers;
• controlling, by the host server, an inspection station to re-inspect said respective integrated circuit fabrication feature of a semiconductor wafer if said respective data received from said inspection station is not within said respective range;
• and
• controlling, by said host server, each of said inspection stations to terminate inspection of said respective lot of semiconductor wafers if said respective data received from said inspection station for a defective semiconductor wafer of said respective lot or semiconductor wafers is not within said respective range after said inspection station re-inspects said respective integrated circuit fabrication feature of said defective semiconductor wafer.