Specific Process Knowledge/Thin film deposition/Deposition of Gold/Roughness of Au

Roughness and uniformity of Au layers

There are several machines at Danchip that can be used to deposit Au. This page show the result of a study about the surface roughness of the Au layers deposited with different machines and parameters.

Experimental

Au was deposited directly on unprocessed Si wafers (on top of the native oxide), and the deposited layers were thereafter examined with AFM.

The deposition parameters were changed, and different equipment was used. Below, AFM pictures of layers deposited with different parameters can be seen.

Results

Layers from Wordentec

The deposition rate was varied between 1.5 Å/s and 10 Å/s. There are no substential differences of the roughness, for different rates. The differences in height of the tallest and lowest structure of the AFM pictures are in all cases between 4 and 6 nm.

The layer deposited in Wordentec is uniform, without any larger structures. Below a 2.5 x 2.5 µm large area of the surface is shown, the difference in hight between the lowest and tallest structure is about 7nm.

E-beam deposited Au layer; deposited in the Wordentec, rate 5 Å/s. The Au surface is uniform, without any large variations of the surface structure.

Layers from Alcatel