System for monitoring wafer carrier

A system for monitoring a wafer carrier, comprising:

• an overhead hoist transport (OHT) vehicle, configured to transport the wafer carrier along a rail;
• a scanner, connected to the rail, wherein the wafer carrier is transported along the rail to pass through the scanner, and the scanner scans at least a lateral portion of the wafer carrier along a vertical direction;
• and
• a processer, coupled to the scanner, wherein the processer receives a scanning result from the scanner after the wafer carrier is scanned, and the scanning result includes information of gas composition within the wafer carrier.

A system for monitoring a wafer carrier, comprising:

• an overhead hoist transport (OHT) vehicle, configured to transport the wafer carrier along a rail in a first direction;
• a scanner, disposed adjacent to the rail in a second direction;
• a shielding structure connected to the scanner;
• and
• a processer, coupled to the scanner,
• wherein the processer receives a scanning result from the scanner after the wafer carrier is scanned, and the scanning result includes information of gas composition within the wafer carrier.