Within-wafer uniformity is traditionally measured by the signal-to-noise ratio (SNR), defined as the estimated standard-deviation of within-wafer measurements o

Spatial Trends In many manufacturing processes, a spatial trend in some response is observed Wafer fabrication: “wafer scale” trends in film thicknesses, electrical properties, etc. resulting from inherent equipment/process asymmetries Key questions: How model? How summarize (e.g. nonuniformity metric)? Image removed due to copyright ...

Signal-to-noise ratio (SNR) enhancement could effec-tively decrease the detection limit by decreasing the influence of the haze signals on the defect signals. The existing method of optimizing the inspection conditions, including beam path and collection channel, can enhance the SNR, but the effect is restrained by the system structure.

2022年4月21日 · The major role of wafer defect inspection systems is to detect and locate defects on a wafer. Systematic defects are primarily caused by the variations of the mask and exposure process and will occur in the same position on the circuit pattern of all the projected dies.

A robust metric for describing within-wafer uniformity is developed and compared with the SNR method. The new metric, termed the integration statistic (I) is shown to be robust to both the location and number of measurements taken on the wafer and has lower variance than the …

2024年9月11日 · 在现代无线通信系统中，信噪比（Signal-to-Noise Ratio, SNR）是一个核心参数，它衡量了信号的强弱与背景噪声的比例。 SNR不仅对无线射频（Radio Frequency, RF）信号的接收质量有直接影响，而且对基带（Baseband, BB）信号的处理也有着至关重要的作用。

A robust metric for measuring within-wafer uniformity has been developed and compared to the traditional SNR metric. The new statistic, referred to as the integration statistic, is based on the integration of the volumetric error between the target and the actual surfaces.

The most common approach is to measure within-wafer uniformity by the signal-to-noise ratio (SNR), defined as the estimated standard-deviation of measurements on the wafer over the mean of those measurements. This metric attempts to summarize the distribution of the measurements by normalizing the standard deviation by the mean.

2024年3月1日 · Optical wafer inspection instruments, such as bright-field microscopy and dark-field microscopy, enable rapid defect inspection through multi-channel acquisition and automated synchronized control. The subsequent defect review employs SEM to analyze the defects based on the defect coordinates coarsely located by optical inspection instruments.

We experimentally confirmed SNR ~ 4 for both line gap and bridge defect detection on 40 nm L/S patterned wafer with the fixed nulling illumination. Advances in the semiconductor industry have led the wafer inspection technology to the limit of nanometer-scale defect detection, which is far beyond the diffraction limit.