Specific Process Knowledge/Thin film deposition/Deposition of Silver/Deposition of Silver

Thermal deposition of Silver

Silver can be thermally evaporated in Wordentec.

The parameters that are good to use for the deposition are listed here below.

(These parameters are changed inside the material section- please contact the process specialist if you are not familiar with this.) For thermal Ag deposition use:

Max power: 6.7 % (With a higher max power, the deposition rate will have large flucturations).

Soak power 1: 4 %

Soak power 2: 6.6 %

Soak time 2: 1 min

This gives a depositon rate of about 2.5 Å/s (to be set in the process parameters).

To get the right thickness measurement of the quartz crystals, use the prameters

Density: 10.5 (thermal evap. of Al 2.7)

Z-ratio: 0.529 (thermal evap. of Al 1.08)

Master Tooling should be set to: 120% (to get the requested layer thickness on the wafer). (Master tooling for Al = 167%).

(15 pellets (1/8" diameter x 1/8" long) were placed in the boat before the evaporation processes were started. More than 4000 Å could be deposited from that amount, without any problem with covered contacts or smilar things.)