Monitoring method for tungsten metal contamination of ion implanter

Abstract

The invention provides a monitoring method for tungsten metal contamination of an ion implanter. The monitoring method comprises the following steps: measuring the mass spectrometry analysis curve ofBF2+, and acquiring the maximum beam value of the mass spectrometry analysis curve of the BF2+; measuring the mass spectrometry analysis curve of WF++, and acquiring the maximum beam value of the massspectrometry analysis curve of the WF++; calculating the ratio of the maximum beam value of the mass spectrometry analysis curve of the WF++ to the maximum beam value of the mass spectrometry analysis curve of the BF2+ so as to obtain the proportion of the tungsten metal contamination when the BF2+ is injected. Compared with a method that an inductively coupled plasma mass spectrometry (ICPMS) isused in general for measuring the metal content of a control wafer to monitor metal tungsten, the monitoring method for the tungsten metal contamination of the ion implanter can be used for relatively fast completing metal contamination monitoring, the time is saved, the control wafer does not need to be consumed, the test stability is good, the metal tungsten monitoring can be better and more faster carried out on the ion implanter, and the monitoring cost is reduced.

Description

technical field [0001] The invention relates to the field of semiconductor integrated circuit manufacturing, and in particular to a monitoring method for tungsten metal contamination of an ion implanter. Background technique [0002] With the development of integrated circuit technology, smaller feature pattern size and closer circuit device spacing are required. Traditional heat spreading has limited the production of advanced integrated circuits. Its limitations lie in lateral diffusion, ultra-shallow junctions, poor doping control, interference from surface contamination, and generation of dislocations. [0003] Ion implantation overcomes the aforementioned limitations of diffusion while offering additional advantages. There is no lateral diffusion during the ion implantation process, the process is carried out at close to room temperature, impurity atoms are placed under the wafer surface, and a wide range of doping concentrations is possible at the same time. With io...

AI Technical Summary

Problems solved by technology

[0006] At present, the ion implanter usually monitors the metal tungsten by measuring the metal content of the control chip with an inductively coupled plasma analyzer (ICPMS), but the ICPMS test has long test time, high cost, easy to be affected by the quality of the control chip, and stable testing How to accurately and timely monitor metal tungsten pollution is a difficult problem

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