公开(公告)号：US20160254119A1

公开(公告)日：2016-09-01

申请号：US15053898

申请日：2016-02-25

Applicant: FEI Company

Inventor： Nikolaos Kontaras ,  Bart Jozef Janssen ,  Cornelis Sander Kooijman ,  Duarte Guerreiro Tome Antunes

IPC: H01J37/244 ,  H01J37/28

CPC classification number: H01J37/244 ,  G01T1/17 ,  H01J37/28 ,  H01J2237/22

Abstract: A system for analyzing an analogue signal comprising randomly spaced events, the event having an event height, comprises: Converting the signal to a series of samples S(t), with t the moment of sampling, thereby forming a sampled, discrete time signal, Detecting the presence of an event, the event detected at t=T, Estimating the event height, Using a model (412, FIG. 5) to estimate a noise contribution N(t) for t=(T−Δ1) to t=(T+Δ2), the noise contribution derived from samples S(t) with t≦(T−Δ1) and/or samples S(t) with t≧(T+Δ2), with Δ1 and Δ2 predetermined or preset time periods having a value such that the event has a negligible contribution to samples taken before (T−Δ1) or after (T+Δ2), Estimating the event height E by integrating the series of samples from (T−Δ1) to (T+Δ2) minus the noise contribution for said samples, E=Σt=(T−Δ1)t=(T+Δ2)S(t)−Σt=(T−Δ1)t=(T+Δ2)N(t)=Σt=(T−Δ1)t=(T+Δ2)[S(t)−N(t)].

Abstract translation: 一种用于分析包括随机间隔事件的模拟信号的系统，所述事件具有事件高度，包括：在t为采样时刻的情况下，将信号转换为一系列样本S（t），从而形成采样的离散时间信号， 检测事件的存在，在t = T处检测到的事件，估计事件高度，使用模型（412，图5）估计t =（T-Δ1）至t =（T-Δ1）的噪声贡献N（t） （T +Δ2），具有t≤（T-Δ1）的样本S（t）和/或具有t≥（T +Δ2）的样本S（t）的噪声贡献，具有Δ1和Δ2预定或预设时间段 具有使得事件对（T-Δ1）之前或之后（T +Δ2）采取的样本的贡献可以忽略不计，通过将来自（T-Δ1）到（T +Δ2）的一系列样本积分来估计事件高度E ）减去所述样本的噪声贡献，E =Σt=（T-Δ1）t =（T +Δ2）S（t）-Σt=（T-Δ1）t =（T +Δ2）N（t）=Σt =（T-Δ1）t =（T +Δ2）[S（t）-N（t）]。

公开(公告)号：US20190362932A1

公开(公告)日：2019-11-28

申请号：US16522308

申请日：2019-07-25

Applicant: FEI Company

Inventor： Nikolaos Kontaras ,  Bart Jozef Janssen ,  Cornelis Sander Kooijman ,  Duarte Guerreiro Tome Antunes

IPC: H01J37/244 ,  H01J37/28

Abstract: The invention relates to a method for analyzing an analogue signal comprising randomly spaced events having an event height. The method includes irradiating a sample with a focused beam of energetic electrons, detecting emission from the sample in response to such irradiation, and converting an analog signal of the emissions to a stationary time signal. The method further includes determining an estimated noise contribution for the stationary time signal, and determining an estimated event height of an event based on the stationary time signal and the estimated noise contribution for the stationary time signal, and determining, based on the estimated event height, an energy of the emission detected by the detector. This method is particularly useful for X-ray detectors, such as Silicon Drift Detectors, used in a SEM. By estimating the noise contribution to the signal, the step height is estimated with improved accuracy.

公开(公告)号：US10692691B2

公开(公告)日：2020-06-23

申请号：US16522308

申请日：2019-07-25

Applicant: FEI Company

Inventor： Nikolaos Kontaras ,  Bart Jozef Janssen ,  Cornelis Sander Kooijman ,  Duarte Guerreiro Tome Antunes

IPC: H01J37/244 ,  G01T1/17 ,  H01J37/28

Abstract: The invention relates to a method for analyzing an analogue signal comprising randomly spaced events having an event height. The method includes irradiating a sample with a focused beam of energetic electrons, detecting emission from the sample in response to such irradiation, and converting an analog signal of the emissions to a stationary time signal. The method further includes determining an estimated noise contribution for the stationary time signal, and determining an estimated event height of an event based on the stationary time signal and the estimated noise contribution for the stationary time signal, and determining, based on the estimated event height, an energy of the emission detected by the detector. This method is particularly useful for X-ray detectors, such as Silicon Drift Detectors, used in a SEM. By estimating the noise contribution to the signal, the step height is estimated with improved accuracy.

公开(公告)号：US10403470B2

公开(公告)日：2019-09-03

申请号：US15053898

申请日：2016-02-25

Applicant: FEI Company

Inventor： Nikolaos Kontaras ,  Bart Jozef Janssen ,  Cornelis Sander Kooijman ,  Duarte Guerreiro Tome Antunes

IPC: H01J37/244 ,  G01T1/17 ,  H01J37/28

Abstract: A system for analyzing an analogue signal comprising randomly spaced events, the event having an event height, comprises: Converting the signal to a series of samples S(t), with t the moment of sampling, thereby forming a sampled, discrete time signal, Detecting the presence of an event, the event detected at t=T, Estimating the event height Using a model (412, FIG. 5) to estimate a noise contribution N(t) for t=(T−Δ1) to t=(T+Δ2), the noise contribution derived from samples S(t) with t≤(T−Δ1) and/or samples S(t) with t≥(T+Δ2), with Δ1 and Δ2 predetermined or preset time periods having a value such that the event has a negligible contribution to samples taken before (T−Δ1) or after (T+Δ2), Estimating the event height E by integrating the series of samples from (T−Δ1) to (T+Δ2) minus the noise contribution for said samples, E=Σt=(T−Δ1)t=(T+Δ2)S(t)−Σt=(T−Δ1)t=(T+Δ2)N(t)=Σt=(T−Δ1)t=(T+Δ2)[S(t)−N(t)].