Improved signal to noise ratio in actinic EUVL mask blank inspection

Yamane, Takeshi; Terasawa, Tsuneo

doi:10.1117/12.978628

Cited by 4 publications

(3 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To address this issue, a full-field ABI verification tool (MIRAI tool) employing an EUV dark-field imaging technique was developed by Selete and EIDEC [7]. On the basis of a high-volume manufacturing (HVM) feasibility study performed with the MIRAI tool, an HVM prototype has been developed by Lasertec and EIDEC [8].…”

Section: Introductionmentioning

confidence: 99%

Background level in extreme-UV dark-field image for mask blank inspection

Yamane

Terasawa

2015

Opt Rev

Self Cite

View full text Add to dashboard Cite

The background level (BGL) in an extreme-UV (EUV) dark-field image for EUV mask blank inspection was analyzed. The background refers to the light scattered by the multilayer roughness of the mask blank, and the variation in the BGL is attributed to random and fixed factors. We found that the BGL variation due to the fixed factor could be successfully reproduced by simulation using surface information obtained by atomic force microscope measurement with the assumption of a multilayer roughness structure. This means that the fixed factor contributing to the BGL variation was found to be speckle noise due to the multilayer roughness. Moreover, this reproduction procedure was found to be valuable for estimating the multilayer roughness structure up to several layers below the surface.

show abstract

Section: Introductionmentioning

confidence: 99%

Background level in extreme-UV dark-field image for mask blank inspection

Yamane

Terasawa

2015

Opt Rev

Self Cite

View full text Add to dashboard Cite

show abstract

“…[1][2][3][4][5][6] To address this issue, a full-filed ABI verification tool (MIRAI-tool) employing a dark field imaging technique was developed by Selete and EIDEC. 7 Based on high-volume manufacturing (HVM) feasibility study performed with the MIRAI-tool, a HVM ABI prototype has been developed by Lasertec and EIDEC. 8 In both cases, the lights scattered from a mask blank surface reach the sensor of a CCD camera, where a defect is captured as a spot signal brighter than the background level (BGL) of its surrounding.…”

Section: Introductionmentioning

confidence: 99%

Performance in practical use of actinic EUVL mask blank inspection

Yamane¹,

Kim²,

Takagi³

et al. 2014

SPIE Proceedings

Self Cite

View full text Add to dashboard Cite

A high-volume manufacturing (HVM) actinic blank inspection (ABI) prototype has been developed, of which the inspection capability for a native defect was evaluated. An analysis of defect signal intensity (DSI) analysis showed that the DSI varied as a result of mask surface roughness. Operating the ABI under a review mode reduced that variation by 71 %, and therefore this operation was made available for precise DSI evaluation. The result also indicated that the defect capture rate was influenced by the DSI variation caused by mask surface roughness. A mask blank was inspected three times by the HVM ABI prototype, and impact of the detected native defects on wafer CD was evaluated. There was observed a pronounced relationship between the DSI and wafer CD; and this means that the ABI tool could detect wafer printable defects. Using the total DSI variation, the capture rate of the smallest defect critical for 16 nm node was estimated to be 93.2 %. This means that most of the critical defects for 16 nm node can be detected with the HVM ABI prototype.

show abstract

“…Phase defect inspection has investigated using DUV wave length inspection tool 1,2 . Actinic wave length inspection tool has developed for phase defect inspection [3][4][5][6] . To evaluate inspection tool sensitivity, PDM is improtant 7 .…”

Section: Introductionmentioning

confidence: 99%

Challenge for under 40nm size pattern making for EUV mask

et al. 2013

View full text Add to dashboard Cite

Extreme Ultraviolet Lithography (EUVL) is a promising technology for the next generation lithography. It will be applied for half pitch 16nm node and beyond. The pattern resolution of recent EUV lithography is around hp20nm and next target is hp16nm. Although present requirement for EUV mask pattern resolution is hp64 nm, there is a special request to make under 40nm size pattern for EUV mask. One of examples is programmed phase defect mask (PDM).Phase defect of EUV blank affects large influence to wafer print result. Blank inspection is one of the key technology for EUV mask fabrication. To evaluate blank inspection tool, program defect mask is essential. Other examples are EUV mask for EUV diffraction exposure tool and EUV microscope evaluation. These masks need absorber pattern resolution of 30nm and smaller. In this paper, we will present process development results targeting 30nm size pattern.Programmed defect size achieved to 20nm width (FWHM: width at half maximum), 1.0nm height, both pit and bump defect. Absorber pattern resolution achieved 30nm half pitch. Not only simple dense line pattern, we fabricated radial pattern and any angle pattern.

show abstract

Improved signal to noise ratio in actinic EUVL mask blank inspection

Cited by 4 publications

References 15 publications

Background level in extreme-UV dark-field image for mask blank inspection

Background level in extreme-UV dark-field image for mask blank inspection

Performance in practical use of actinic EUVL mask blank inspection

Challenge for under 40nm size pattern making for EUV mask

Contact Info

Product

Resources

About