ON MASS-SPECTROSCOPIC AND EMISSION-SPECTROSCOPIC CVD PROCESS MONITORING OF ORGANOMETALLICS O-2 DISCHARGES/

Mass spectroscopic analysis of neutrals and ions from a deposition pla sma shows that the decomposition of the organometallic precursor compo unds [La(thd)3, Cu(acac)2, and Al isopropoxide] in the plasma starts w ith the abstraction of complete ligands. The mass spectra of plasma io ns sensitively indicate the incomplete oxidation of the organic fragme nts with increasing organometallic partial pressure. The concentration of carbon-rich ions in the oxygen-based deposition plasma correlates with the carbon content of the deposited oxide films. Specific emissio ns of the precursor compounds (e.g., Cu atomic lines and LaO bands) ca n be used to monitor the precursor partial pressure; however, there is some interference with sputter emission from the deposited films. Dur ing La2O3 deposition, optical emission of oxidation products (eg., OH, CO, CO2 bands) was used to regulate the precursor partial pressure in the discharge with a closed-loop control circuit.