One of the problems that arise when aluminum is deposited with a sputter system is that it causes discoloration in thin films over a certain thickness.
When the composition of the discolored thin film is checked, aluminum oxide is confirmed. This leads to suspicion of chamber leakage, and it takes a lot of time to check for leaks in chambers that are not leaked.
Of course, there may be leaks in the sputter chamber. However, when there is a leak, the thin film is usually formed as an iridescent light. The thickness of the thin film is not constant, and the reproducibility and composition of the thin film produced are unstable.
When the composition of the discolored thin film is checked, aluminum oxide is confirmed. This leads to suspicion of chamber leakage, and it takes a lot of time to check for leaks in chambers that are not leaked.
Of course, there may be leaks in the sputter chamber. However, when there is a leak, the thin film is usually formed as an iridescent light. The thickness of the thin film is not constant, and the reproducibility and composition of the thin film produced are unstable.
-----------------------------
If a thin film of oxide is formed in the thin film even in the absence of leakage, the outgassing of the chamber should be suspected.
The discoloration of the film due to outgassing usually begins to be identified when it reaches a certain thickness. The thickness that begins to be identified expands to an increasingly thinner area, and ultimately becomes visible in very thin films.
When this phenomenon occurs, the ROR test result usually shows the result of E-4 or higher, and the limit vacuum of the chamber also takes a lot of time, so that it can be judged that a complex problem occurs.
The discoloration of the film due to outgassing usually begins to be identified when it reaches a certain thickness. The thickness that begins to be identified expands to an increasingly thinner area, and ultimately becomes visible in very thin films.
When this phenomenon occurs, the ROR test result usually shows the result of E-4 or higher, and the limit vacuum of the chamber also takes a lot of time, so that it can be judged that a complex problem occurs.
------------------------------
In order to reduce the effect of outgassing, it is advisable to increase the deposition rate as much as possible by depositing aluminum thin film by sputtering.
And, the limit vacuum degree and the process pressure should be minimized. This is also related to the deposition rate and it is advisable to finish the process before the temperature of the chamber is raised.
And, the limit vacuum degree and the process pressure should be minimized. This is also related to the deposition rate and it is advisable to finish the process before the temperature of the chamber is raised.
