Professional Experience of using Evaporation Boat

Professional Experience of using Evaporation Boat
Installation of evaporation boat
Boat clamping is very important for the better evaporation and increased boat life. Evaporation Boats are clamped on copper electrode and there are two types of clamping-They are Side clamping  and Top clamping .Evaporation Boats
Attention:

1- Use graphite foil between boat and electrode. Thisis used for two purposes. Firstly, adjustment of tightness and secondly, relive the thermal stress because of the different CTE for uniform contact.

2- Keep proper contact between evaporation boat and electrode, so as to ensure good electrical contact. If it is too loose, it will cause current instability at both ends of boat. As a result it can cause an electrical spark. Also, boat will not have enough power resulting in evaporation boat temperature is too low and spreading liquid aluminum which cannot evaporate. If it is too tight, when the evaporation boat is heated, thermal expansion will not easy and it will be difficult to release thermal stress. As a result this may deform the boat or even cause the boat crack and fracture.

Every time before installation of a new boat, carefully clean up the two copper electrodes. Also, the aluminum and graphite tape must be thoroughly cleaned.

3- Make sure of the boat alignment and there should be no gap between boat and electrode otherwise the boat will distort during heating. This will lead to poor contact causing spark and boat cracking.