How HMDS is Used in Surface Science

Hexamethyldisilazane (HMDS) is a colorless, flammable liquid with a unique chemical structure. It is frequently used in surface science as a primer agent to treat the surfaces of silicon wafers and make them more suitable for adhesion with a photoresist. Using HMDS is also common as a pre- and post-treatment method for surface coating applications. In this blog post, we will look at how HMDS is used in surface science and the benefits of doing so.

What is Surface Science?

Surface science is the study of the chemical and physical properties of solid surfaces and interfaces, including their dynamics, functionality, and structure. It involves gaining a further understanding of the surface properties of two phases, which could be solid-gas, solid-liquid, solid-vacuum and liquid-gas interfaces. Surface science is critical in a range of industries, from semiconductor manufacturing to biotechnology and materials science, because of its unique properties.

HMDS in Surface Science

HMDS has several valuable uses in surface science as it can be used as a coating material, a modification agent, or a surface passivation agent. We will discuss each of these applications in more detail below.

Coating Material

HMDS is used as a coating material in the semiconductor industry before applying a photoresist. When HMDS is deposited on a surface, it leaves methyl groups behind. These then bond with the OH molecules on the silicon surface and help develop a strong adhesion when a photoresist is applied.

Modification Agent

Surface modification of certain compounds can be conducted with HMDS as it is feasible and only has ammonia as a byproduct. The most commonly modified surfaces with HMDS include silica aerogels, which are rendered hydrophobic during the process.1 The option to modify silica aerogels is necessary for areas of semiconductor and pharmaceuticals as changing their chemical properties make them more suitable for specific applications.2 Modifying the surface of materials can make them more compatible with surface analysis techniques such as scanning electron microscopy (SEM) and transmission electron microscopy (TEM). 

Surface Passivation Agent 

Surface passivation is a chemical process conducted to increase the surface properties of a material so it better resists corrosion and contamination. When HMDS is used for surface passivation, it develops a layer that acts as a coating. This process is used after a product has been fabricated and helps produce a more robust product.

Platypus Technologies and HMDS

Platypus Technologies are experts in the world of surface science, and we offer a range of services in cell culture, electrochemistry, metal coatings, nanotechnology and other similar areas. In surface science and photolithography applications, we use HMDS in treatment preparation methods and protective coatings to enhance a material’s properties. 

Contact a member of Platypus Technologies today to learn more about the many applications of HMDS in surface science. 

References

  1. https://www.sciencedirect.com/science/article/abs/pii/S0896844609003696
  2. https://www.sciencedirect.com/book/9781845695262/materials-for-energy-efficiency-and-thermal-comfort-in-buildings