Using Trimethylsilanol for creating Hydrophobic Liner compared to other Silicon Compounds

Semiconductors are crucial to computing, healthcare, military, and transportation industries. The deposition step in semiconductors– wherein thin layers of materials are applied onto the surface– is critical, requiring a liner with similar hydrophilicity to incoming materials that are required to be deposited. Without the liner, materials can flake, creating problems such as particle contamination and incomplete coverage. Several materials, such as chlorotrimethylsilane (CTS), bromotrimethylsilane (BTS), bis(trimethylsilyl)amine, and trimethylsilyl methanesulfonate, can convert hydrophilic to hydrophobic surfaces of the silica wafer. However, these materials can be cost-intensive, produce extremely strong acid by-products, or create unwanted strong and sharp odors, such as ammonia. To investigate the relationship between the acidity of reaction byproducts and the degree of liner hydrophobicity, we hypothesized that bromotrimethylsilane, chlorotrimethylsilane, and trimethylsilyl methanesulfonate, which produce a strong acid as a by-product, would have a lower contact angle compared to trimethylsilanol (TMS), which only creates water in the process of creating a hydrophobic liner. We found that TMS yields better hydrophobicity due to not deviating the pH of the wafer during coating. TMS only creates water in the process, which does not break the siloxane bond to reverse the reaction, unlike other chemicals that can. Thus, it follows that TMS could be an excellent choice for the deposition liner compared to other chemicals due to lowering the reverse reaction, which can lower the contact angle. The significance of these findings has the potential to lead industries to enhance uniformity and reliable adhesive properties in coatings with lower contact angles in reverse reactions.