A carrier is a specially designed transport and process holder for accommodating wafers, solar cells, or other products. It positions the substrates precisely and reproducibly during wet-chemical processes and enables their safe, automated transport through the wet-chemical system. The carrier is an integral part of the equipment concept and contributes significantly to process stability, uniform wetting, and high product quality.

In semiconductor manufacturing, different carrier concepts are used, including conventional process carriers, low-mass carriers (LMC), and carrierless approaches. For reliable process execution in wet-chemical equipment, the tank geometry, substrate guidance, and flow management (fluid impingement/flow distribution) must be specifically designed for the respective carrier system.

Each concept comes with different technical boundary conditions: In carrierless concepts, the focus is primarily on reliable gripping, handling, and defined substrate placement within the tank. With LMC and process carriers, the fluid-dynamic design at the carrier’s contact and shielding points is particularly critical, as these areas can influence local chemical supply, wetting behavior, and thus process uniformity.

In addition, a distinction is made between transport carriers and process carriers. Transport systems such as FOUP (Front Opening Unified Pod) or SMIF (Standard Mechanical Interface) are primarily used for contamination-controlled logistics and storage and are typically not introduced into the wet-chemical process equipment.

Carriers must meet the specific process requirements of the respective wet-chemical system. They are resistant to the chemicals used, process temperatures, and cycle times, fulfill stringent cleanliness requirements, and are free of particle generation. As a result, they support stable processes, minimize contamination risks, and contribute to the high product quality of wet benches.