Method and system of surface topography measurement for lithography

A method, comprising:

• providing a workpiece to a semiconductor apparatus, the workpiece comprising a material layer, wherein the material layer comprises a plurality of strips, wherein each of the strips includes a first exposure field configured to be exposed in a first direction and a second exposure field configured to be exposed in a second direction different from the first direction, wherein the first exposure field and the second exposure field are adjacent to each other in the respective strip;
• scanning the first exposure field of each of the plurality of strips along a first route and a second route different from the first route within the respective strip to generate first topography measurement data;
• scanning the second exposure field of each of the plurality of exposure strips along the first route and the second route within the respective strip to generate second topography measurement data;
• and
• exposing the first exposure field and the second exposure field in the first direction and the second direction, respectively, according to the first topography measurement data and the second topography measurement data, respectively.

A semiconductor apparatus, comprising:

• a stage configured to support a workpiece, the workpiece comprising a material layer, wherein the material layer includes a strip having a first exposure field configured to be exposed in a first direction and a second exposure field configured to be exposed in a second direction different from the first direction;
• a level sensor device over the stage;
• and
• a control unit configured to:
• move the workpiece by the stage to a first site of the semiconductor apparatus;
• scan the first exposure field along a first route and a second route, different from the first route, in the strip to generate first topography measurement data;
• scan the second exposure field along the first route and the second route in the strip to generate second topography measurement data;
• move the workpiece by the stage to a second site of the semiconductor apparatus;
• and
• perform an exposure operation on the first exposure field and the second exposure field according to the first topography measurement data and the second topography measurement data.