Understanding the Annealing Process for Germanium Wafers

Manufacturing devices with a germanium wafer requires careful attention to surface preparation. When annealing silicon wafers, there are several methods to be explored, including quartz tube lamps, induction heating, and resistance coating—but germanium wafers come with unique properties and extra surface preparation requirements.

Let’s review the characteristics of germanium substrates and why it is important to use a suitable annealing recipe for the application.  

What is Wafer Annealing?  

Wafer annealing is a process that repairs atomic level disorder from steps like ion implantation. This process is crucial for ensuring the quality and performance of semiconductor materials.  

How Do You Anneal Germanium Wafers?

Germanium wafers come with unique requirements, making the list of effective methods for effective germanium wafer annealing restricted:

• Post-metallization annealing: A good process is post-metallization annealing in nitrogen at 400 degrees Celsius. The FWHM of the XRD peak decreases as the concentration of Ge increases. Additionally, the presence of Ge atoms contributes to stress.

• Annealing at 580°C: The Ge layer experiences partial agglomeration following 30 minutes of annealing at 580 degrees Celsius. Small particles are created on top of the continuous Ge layer, and large particles are created in a narrow channel. Even longer anneals at this temperature do not result in total agglomeration.

• Annealing at 600°C: The Ge particles have a comparatively small average size and form a uniformly distributed surface at 600 degrees Celsius

• Laser annealing: Another option for a high-molecular-weight BCP is laser annealing. This method allows more control over time and space than with traditional oven annealing.  

Learn About Our Processes for Annealing Germanium Wafers

Wafer annealing is a crucial step in wafer manufacturing. It helps relieve stress in substrates, activate or move dopants, and densify deposited or grown films, among other benefits. Therefore, it’s crucial when creating devices like transistors or chips out of germanium wafers.

If you want to learn more about our manufacturing processes, contact Wafer World, and let’s chat!