A Method for Monitoring the Stability and Uniformity of an Ion Implanter

Abstract

The invention discloses a method for monitoring the stability and the uniformity of an ion implanter. The method includes the steps that firstly a germanium amorphous barrier layer is formed on the surface of a sample wafer substrate to be measured so as to reduce the ion implantation depth, in the monitored ion implanter, of subsequent wafers, high temperature annealing is conducted so as to form doped silicon germanium alloy with good conductivity on the surfaces of the wafers, therefore, common probes of a four-probe tester can be directly used for measuring RS accurately, and the effect that the stability and the uniformity of the ion implanter are monitored accurately is achieved. Due to the application of the method, the measuring cost is lowered, and the service life of a measuring machine is prolonged. Meanwhile, according to the method, the accuracy and the stability of RS measurement are effectively improved, the downtime risk caused by misjudgment is greatly reduced, and the productivity of the ion implanter is improved.

Description

technical field [0001] The present invention relates to a method for monitoring the performance of an ion implanter in semiconductor manufacturing, more specifically, to a method for accurately measuring the sheet resistance of a wafer by reducing the depth of ion implantation to monitor the stability of an ion implanter and uniformity. Background technique [0002] The development of highly integrated circuits requires smaller feature pattern sizes and closer circuit device pitches. And thermal spreading has limitations on the production of advanced 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 a...

AI Technical Summary

Problems solved by technology

Compared with the ordinary probe head, the sharper probe head of this kind of probe is expensive and has a shorter service life, only about two months

While increasing the measurement cost, it will also increase the maintenance frequency of the measurement machine

Moreover, when using such a sharp probe head, it is also easy to be unstable due to the unstable operation of the ion implanter to be measured, or the unstable measurement performance caused by the end of the service life of the probe head. As a result, the wafer measurement results exceeded the specifications, resulting in misjudgment of the status of the ion implanter and downtime

This disrupted the normal operation of the ion implanter and further impacted the machine's throughput

How to more accurately monitor the stability and uniformity of the ion implanter, improve the life of the measuring machine, and avoid the phenomenon of downtime caused by inaccurate measurement and affecting production capacity is an urgent issue for us to solve.

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