Epitaxial temperature testing and monitoring structure and forming method

Abstract

The invention provides an epitaxial temperature testing and monitoring structure and a forming method. The method comprises the steps that a dielectric layer is grown on a substrate; monitoring structure windows including first openings are formed in the dielectric layer, the sizes of the first openings are equal, and the first distances of the first openings are fixed; part of exposed substrate is consumed away, then an oxidation layer is grown, the dielectric layer and the oxidation layer are removed, and monitoring windows with equal sizes are formed, wherein the second distances of the monitoring windows have step differences; testing structures are formed on the monitoring windows through an epitaxy technique, and image data in the direction of epitaxial distortion occurring in third openings in the testing structures and the third distances between the third openings are obtained; only the temperature of the epitaxy technique is changed, the steps are repeated, the image data obtained every time are processed and correspond to the changed temperature of the epitaxy technique respectively, and therefore a relational graph is formed, a monitoring measure is formed, epitaxial temperature can be monitored simply and efficiently, the operability is strong, and the epitaxial temperature can be monitored fast and effectively to reduce product risks caused by temperature deviation.

Description

technical field [0001] The invention belongs to the technical field of semiconductor manufacturing technology, and in particular relates to an epitaxial temperature testing and monitoring structure and a forming method. Background technique [0002] In the integrated circuit manufacturing process, the epitaxial process (Epitaxy) refers to the growth of conductive type, The process of a new single crystal layer whose resistivity, thickness, lattice structure, integrity and other parameters meet the product structure requirements, this layer of single crystal layer is called an epitaxial layer. [0003] According to the planar anisotropy of crystallographic plane growth, the newly grown single crystal layers must be sequentially grown strictly along the original crystal axis direction of the substrate. In the front process of epitaxial layer formation, the surface discontinuity caused by oxidation during the annealing process of the buried layer (NBL or BL) will also propagat...

AI Technical Summary

Problems solved by technology

Due to the loss of the working end of the thermocouple, the insensitivity of the thermomagnetic effect, and the error of the compensation wire correction, the temperature of the epitaxial process will fluctuate, and it may be high or low for a long time, or the function of the thermocouple may be affected. Sustained attenuation occurs, which poses a risk to product quality if temperature changes are not detected during the thermocouple detection cycle

The epitaxial thickness and resistivity usually monitored in the epitaxial process cannot be alarmed when the temperature deviation is small. If the product parameters cannot be adjusted in time, it will cause abnormal quality of large-scale products.

In order to avoid the problem that the thermocouple cannot monitor the epitaxial temperature change in time during the thermocouple detection period, generally only by increasing the frequency of thermocouple calibration and replacing the thermocouple to reduce the risk of temperature deviation, but due to the high cost of frequent thermocouple replacement, thermoelectric The couple calibration process is complicated, so it has a great impact on cost and production capacity

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