Tetramethylammonium hydroxide (TMAH) solution is used as a CMP (Chemical Mechanical Polishing) pre-cleaner in wafer production or as a developer in photolithography in the semiconductor field. In order to completely wet the wafer surface , a surfactant is usually added to the TMAH solution to reduce its surface tension. Ensures a stable and surface geometry-independent etching process.
Dynamic surface tension (wetting behavior that changes over time) has a very . Static measurement methods such as hanging tabs and pull rings are not suitable for the analysis of this kind of problem, because They measure static surface tension rather than dynamic surface tension. In addition, after measurement with the static method , a very complicated cleaning of the test equipment is required, which consumes a lot of time.
German SITA company provides different solutions to detect the surface tension of bath formulations according to different application fields. Based on the innovative bubble pressure method, SITA tensiometers can accurately and quickly measure dynamic surface tension, from dynamic to quasi-static surface tension.
SITA DynoTester is a very flexible and portable hand-held surface Tension Tester, which is very suitable for quality monitoring in the process. It can perform on-site measurement, the test time is short, and the test result can be compared with the required value immediately . Therefore, the SITA DynoTester provides a quick . The operation is simple, no professional experience is required, and all functions of the instrument can be realized through the keys on the instrument .
For high-demand TMAH solutions and the need for continuous monitoring of test results, SITA recommends using the process monitoring system - SITA Clean Line ST. This system is directly integrated in the process , regularly measures the surface tension and automatically compares the data within the set range, so we can take relevant measures in a short time after the surfactant concentration exceeds the limit value. The device can store at least one full year of test data, and if long-term data storage is required, the data can be transferred to a computer via the USB port.
SITA's Surface Tensiometer can reliably monitor the quality of the bath solution, and establish a good foundation for the development and cleaning process to obtain high-quality results. In addition, surface tension measurement can avoid excessive use of surfactants, thereby reducing production costs.
