A method for monitoring doping concentration in high temperature furnace tube

Abstract

The invention discloses a method for monitoring doping concentration in a high-temperature furnace tube, comprising the following steps: integrating an easy-to-implement diffusion operation into a MOSstructure containing a substrate piece to be monitored such that the test areas O1 and O2 have different doping profiles, further testing quasi-static C-V characteristics and high-frequency C-V characteristics of the area O2 and quasi-static C-V characteristics and high-frequency C-V characteristics of the area O1 of the MOS structure, calculating flat-band voltage values of the areas O1 and O2 of the MOS structure by performing data analysis on the measured data to obtain a flat-band voltage difference deltaVoFB of the substrate piece in the region O1 and the region O2, and substituting thedeltaVoFB into the function relationship of the flat-band voltage difference and the ion implantation dose to quickly calculate the corresponding equivalent ion implantation dose, wherein the equivalent ion implantation dose is the doping concentration of boron ions or phosphorus ions actually introduced into the substrate piece to be monitored for diffusion this time.

Description

technical field

[0001] The invention relates to doping monitoring in the manufacture of semiconductor integrated circuits, in particular to a method for monitoring doping concentration in a high-temperature furnace tube. Background technique

[0002] In the manufacture of semiconductor integrated circuits, the diffusion method is usually used to modulate the impurity doping concentration and junction depth in a specific region to meet product parameter requirements. Therefore, ensuring the consistency of the concentration of boron and phosphorus impurities in the online diffusion process plays a key role in the stability of the product process. Especially for the small line width product process, the doping impurity concentration on the surface of the product is usually low. If the surface of the product is contaminated by a small amount of boron and phosphorus impurities or the diffusion conditions fluctuate during the tape-out process, the threshold voltage and breakdown c...

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