Run-to-run CD error analysis and control monitoring of effective dose and focus

Asano, Masafumi; Fujisawa, Toshio; Izuha, Kyoko; Inoue, Soichi

doi:10.1117/12.482807

Cited by 8 publications

(4 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Simultaneous focus and exposure control in lithography is effective for CD control [5][6][7][8] . We tried to apply scatterometry to CD control by utilizing the ability of 2D profile monitoring.…”

Section: Application For Advanced Process Controlmentioning

confidence: 99%

Usage of profile information obtained with scatterometry

et al. 2005

Self Cite

View full text Add to dashboard Cite

Scatterometry, a non-destructive optical metrology, provides information on cross-sectional pattern profiles, including pattern height, sidewall angle and linewidth. Compared with other non-destructive metrology tools, such as the atomic force microscope (AFM) and CD-SEM, scatterometry offers the advantages of high throughput and superior repeatability. We have applied scatterometry to the monitoring of the depth of Shallow Trench Isolation (STI) for the analysis of complicated stack. We obtained sufficient measurement accuracy by optimizing a model.In addition, we propose the application of scatterometry to post-lithography monitoring for advanced process control (APC). A regression model was established to derive effective dose and focus from the change of photoresist profile monitored by means of scatterometry. In our experiment using an ArF scanner, we obtained sufficient measurement repeatability of dose and focus.

show abstract

Section: Application For Advanced Process Controlmentioning

confidence: 99%

Usage of profile information obtained with scatterometry

et al. 2005

Self Cite

View full text Add to dashboard Cite

show abstract

“…6 Monitoring of defocus and effective dose are useful for CD control. 7 Therefore, it may be worthwhile to introduce scatterometry to the manufacturing process flow. To avoid the increase of turn-around-time (TAT) of chip fabrication caused by addition of inspection steps, we would like to propose a CD metrology flow in which a scatterometer and a CD-SEM are combined as shown in Fig.…”

Section: The Combined Use Of Scatterometer and Cd-semmentioning

confidence: 99%

In-line CD metrology with combined use of scatterometry and CD-SEM

et al. 2006

Self Cite

View full text Add to dashboard Cite

Measurement characteristics in scatterometry and CD-SEM for lot acceptance sampling of inline critical dimension (CD) metrology were investigated by using a statistical approach with Monte Carlo simulation. By operation characteristics curve analysis, producer's risk and consumer's risk arising from sampling were clarified. Single use of scatterometry involves a higher risk, such risk being particularly acute in the case of large intra-chip CD variation because it is unable to sufficiently monitor intra-chip CD variation including local CD error. Substituting scatterometry for conventional SEM metrology is accompanied with risks, resulting in the increase of unnecessary cost. The combined use of scatterometry and SEM metrology in which the sampling plan for SEM is controlled by scatterometry is a promising metrology from the viewpoint of the suppression of risks and cost. This is due to the effect that CD errors existing in the distribution tails are efficiently caught.

show abstract

“…The efficacy of this approach to in-line CD control has been demonstrated. 8 As reported in the literature, determination of effective dose and defocus has required the measurement of at least two pattern dimensions (CDs) having distinctive dependence on dose and/or defocus. Distinctive dependence is guaranteed by the pairing of pattern dimensions that exhibit differing dose and focus response.…”

Section: CD Profile Effective Dose and Defocusmentioning

confidence: 99%

A new approach to pattern metrology

Ausschnitt

2004

Metrology, Inspection, and Process Control for Microlithography XVIII

View full text Add to dashboard Cite

We describe an approach to pattern metrology that enables the simultaneous determination of critical dimensions, overlay and film thickness. A single optical system captures nonzero-and zero-order diffracted signals from illuminated grating targets, as well as unpatterned regions of the surrounding substrate. Differential targets provide in situ dimensional calibration. CD target signals are analyzed to determine average dimension, profile attributes, and effective dose and defocus. In turn, effective dose and defocus determines all CDs pre-correlated to the dose and focus settings of the exposure tool. Overlay target signals are analyzed to determine the relative reflectivity of the layer pair and the overlay error between them. Compared to commercially available pattern metrology (SEM, optical microscopy, AFM, scatterometry and schnitzlometry), our approach promises improved signal-to-noise, higher throughput and smaller targets. We have dubbed this optical chimera MOXIE (Metrology Of eXtremely Irrational Exuberance).

show abstract

Run-to-run CD error analysis and control monitoring of effective dose and focus

Cited by 8 publications

References 5 publications

Usage of profile information obtained with scatterometry

Usage of profile information obtained with scatterometry

In-line CD metrology with combined use of scatterometry and CD-SEM

A new approach to pattern metrology

Contact Info

Product

Resources

About