1. Field of the Invention
Embodiments of the present invention generally relate to the fabrication of integrated circuits. More particularly, embodiments of the invention relate to a method of seasoning a chamber and depositing a low dielectric constant layer in the chamber.
2. Description of the Related Art
In the fabrication of integrated circuits and semiconductor devices, materials such as oxides, e.g., carbon-doped oxides, are typically deposited on a substrate in a processing chamber, such as a deposition chamber, e.g., a chemical vapor deposition (CVD) chamber. The deposition processes typically result in deposition of some of the material on the walls and components of the deposition chamber. The material deposited on the chamber walls and components can affect the deposition rate from substrate to substrate and the uniformity of the deposition on the substrate. The material deposited on the chamber walls and components can also detach from the chamber components and create contaminating particles that can damage or destroy semiconductor devices.
Particle contamination within the chamber is typically controlled by periodically cleaning the chamber using cleaning gases, typically fluorinated compounds, that are excited by inductively or capacitively coupled plasmas. Cleaning gases are selected based on their ability to bind the precursor gases and the deposited material formed on the chamber components in order to form volatile products which can be exhausted from the chamber, thereby cleaning the process environment of the chamber.
Once the chamber has been sufficiently cleaned of the process gases and the cleaning by-products have been exhausted out of the chamber, a seasoning step is performed to deposit a film onto components of the chamber forming the processing region to seal remaining contaminants therein and reduce the contamination level during processing. This step is typically carried out by depositing a seasoning film to coat the interior surfaces forming the processing region in accordance with the subsequent deposition process recipe.
Typically, seasoning films have been deposited in deposition chambers using gas mixtures identical to the gas mixtures used in the deposition processes performed in the chamber after chamber seasoning. However, it has been found that seasoning films deposited from gas mixtures have identical components in identical ratios to the gas mixtures used in subsequent deposition processes, such as the deposition of carbon doped oxides, can crack or peel off from the interior surfaces of the deposition chamber, creating contaminating particles in the chamber.
Therefore, there remains a need for a method of seasoning a deposition chamber in which the formation of contaminating particles from the seasoning film is minimized.