Secondary Ion Mass Spectrometry Qualitative Science Application In Semiconductor Doping Process

From 1960 s to now,with the development of integrated circuit manufacturing process,doping process technology is also in progress.According to the shrink of device critical size request ion doping more accurately.The ion dope accuracy will directly impact the device all electrical parameters performance.So the IC failure phenomenon happens now and then which due to minor abnormality of doping.How to qualitative and quantitative analyze out the minor abnormality of ion dope and provide the accurately early detection data will be pivotal for process improvement.SIMS(Secondary Ion Mass Spectroscopy)is a method using mass spectrum analyze secondary ion that bombard by the primary ion beam,which can collect the materials' surface or the depth profile elementary information.SIMS have been the important analytical method due to the obviously advantages on mass resolution,spatial resolution and UHV(Ultra High Vacuum)condition.SIMS with wider application,but all the time,it lacks systemic analytical process and quantized reference data for doping parameters' minor shift,especially the early detection of critical doping dosage and angle parameters.This paper major researches the root cause and principle of doping parameter abnormality.Doping species contamination maybe caused by implanter low mass resolution.Energy contamination always caused by residue gas impact on ion charge situation before accelerated.Improper Main chamber vacuum press compensation is the obviously cause of dosage bad uniformity.The angle abnormality because of disk control parameter setting shift and the disk cone effect.Refer to above experiment and analysis,this paper performs a further improvement and optimization on SIMS analytical process of doping parameters.Especially,this paper proposes the early detection method of dosage and angle which can provide more accuracy data for doping parameters optimize direction.