Patent ID: 7615120

Claim:
An atomic layer deposition system comprising: a mass delivery control system configured and arranged to deriver precise quantities of gaseous mass of at least one precursor gas to a processing chamber, the mass delivery control system including: (i) a delivery chamber including an inlet and outlet; (ii) an inlet valve, connected to the inlet, configured and arranged so as to control the flow of precursor gas into the delivery chamber through the inlet (iii) an outlet valve, connected to the outlet and configured and arranged so as to control the flow of gas from the delivery chamber through the outlet; and (iv) a controller configured and arranged to control the inlet and outlet valves, wherein the controller is configured and arranged to calculate, when the outlet valve is open, the quantity of gaseous mass exiting the outlet valve and to close the outlet valve when the calculated quantity of gaseous mass reaches a mass setpoint; and a process chamber, coupled to the outlet and configured and arranged to receive the gaseous mass from the mass delivery control system wherein the amount of mass of gas flowing from the delivery chamber, Δm at time t*, is determined by the controller as follows: Δm=m ( t 0 )− m ( t *)=( V/R )[( P ( t 0 )/ T ( t 0 ))−( P ( t *)/ T ( t *))], wherein m(t 0 ) is the mass of the gas in the delivery chamber at time=t 0 when the gas within the delivery chamber is at a state of equilibrium, m(t*) is the mass of the gas in the delivery chamber at time=t*, V is the volume of the delivery chamber, R is equal to the ideal gas constant (J/Kg−K), P(t 0 ) is the pressure in the delivery chamber at time=to, P(t*) is the pressure in the deliver chamber at time=t*, T(t 0 ) is the temperature in the delivery chamber at time=to, T(t*) is the temperature in the delivery chamber at time=t*.