Cryo pump based HV evaporator

A cryo-pump based HV evaporator has been setup to prepare thin films under hydrocarbon free high vacuum condition. It is used extensively for the preparation of thin film multi-layers for materials science experiments, targets of metals of high melting point with low vapour pressure and various other applications which require hydrocarbon free evaporation environment.


Evaporation source:

A 4-pocket electron gun and 6 kW power supply.

Resistive heating arrangement.

Online thickness measurement:
Dual crystal thickness monitor.
Programmable deposition controller.

The electron gun power supply is interface to this controller which controls the output power of the e-gun by PID method according to the programmed deposition schedule.

The thickness of a film can be defined within an accuracy of 1 Å and the rate of deposition can be controlled with accuracy of 0.1 Å/s.

Pumping station:
1. Scroll pump (for roughing of evaporator and backing of turbo molecular pump).

2. Turbo molecular pump.
3. Cryo pump.
Base pressure is 2x10-8 mbar.

Substrate heater: Heating upto 400oC.

Residual Gas Analyze (RGA):

Pfeiffer Prisma QMS200, 200amu RGA installed to monitor partial pressure of gases in the evaporator.