Specific Process Knowledge/Characterization/Dektak XTA - Revision history

Reet at 11:33, 7 July 2025

2025-07-07T11:33:49Z

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	=Dektak XTA (Stylus Profiler)=		=Dektak XTA (Stylus Profiler)=

			[[image:Dektak XTA new.JPG\|275x275px\|right\|thumb\|Dektak XTA. Now in cleanroom C-1, at time of photo it was somewhere else.]]

	The Dektak XTA stylus profiler from Brüker is used for profiling surfaces of samples with structures in the micro- and nanometer range. The size of the structures that can be measured is limited by the tip dimensions.		The Dektak XTA stylus profiler from Brüker is used for profiling surfaces of samples with structures in the micro- and nanometer range. The size of the structures that can be measured is limited by the tip dimensions.
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	A profile measurement can be done across a specific structure by using a high magnification camera to locate the structure. It is also possible to program the stylus to measure in several positions, defined with respect to some deskew points. [[Specific_Process_Knowledge/Characterization/Stress_measurement\|Stress measurements]] of thin films can be done by measuring the wafer bow. However, for predefined measurement programs or stress measurements, we recommend the [[Specific_Process_Knowledge/Characterization/Tencor_P17\|P17 profiler]].		A profile measurement can be done across a specific structure by using a high magnification camera to locate the structure. It is also possible to program the stylus to measure in several positions, defined with respect to some deskew points. [[Specific_Process_Knowledge/Characterization/Stress_measurement\|Stress measurements]] of thin films can be done by measuring the wafer bow. However, for predefined measurement programs or stress measurements, we recommend the [[Specific_Process_Knowledge/Characterization/Tencor_P17\|P17 profiler]].

			The user manual, quality control procedure and results, technical information and contact information can be found in [http://labmanager.nanolab.dtu.dk/function.php?module=Machine&view=view&mach=304 '''LabManager'''].
	The user manual, quality control procedure and results, technical information and contact information can be found in [http://labmanager.~~danchip~~.dtu.dk/function.php?module=Machine&view=view&mach=304 '''LabManager'''].
	<br>		<br>

	Information on measurement accuracy and reproducibility for the stylus profilers may be found [[Specific Process Knowledge/Characterization/Stylus Profiler Measurement Uncertainty\|here]]		Information on measurement accuracy and reproducibility for the stylus profilers may be found [[Specific Process Knowledge/Characterization/Stylus Profiler Measurement Uncertainty\|here]].
	<br>		<br>
	==Performance and Process Parameters==		==Performance and Process Parameters==

	~~[[image:Dektak XTA new.JPG\|275x275px\|right\|thumb\|Dektak XTA. Now in cleanroom C-1, at time of photo it was somewhere else.]]~~

	{\| border="2" cellspacing="0" cellpadding="10"		{\| border="2" cellspacing="0" cellpadding="10"

Reet: /* Performance and Process Parameters */

2025-07-07T11:21:22Z

Performance and Process Parameters

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	*5 µm 45<sup>o</sup> cone		*5 µm 45<sup>o</sup> cone
	\|-		\|-
	!style="background:silver; color:black" align="left" rowspan="5" valign="top" \|Substrates		!style="background:silver; color:black" align="left" rowspan="5" valign="top" \|Substrates and films
	\|style="background:LightGrey; color:black"\|Substrate size		\|style="background:LightGrey; color:black"\|Substrate size
	\|style="background:WhiteSmoke; color:black"\|		\|style="background:WhiteSmoke; color:black"\|
	*Up to 6"		*Up to 6"
	\|-		\|-
	\| style="background:LightGrey; color:black"\|~~Substrate materials~~ allowed		\| style="background:LightGrey; color:black"\|Materials allowed
	\|style="background:WhiteSmoke; color:black"\|		\|style="background:WhiteSmoke; color:black"\|
	*All materials that do not stick to the tip or leave residues		*All materials that do not stick to the tip or leave residues

Reet: /* Performance and Process Parameters */

2025-07-07T11:16:42Z

Performance and Process Parameters

Reet: /* Performance and Process Parameters */

2025-07-07T11:12:49Z

Performance and Process Parameters

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	\|style="background:LightGrey; color:black"\|Height accuracy z (95 % confidence)		\|style="background:LightGrey; color:black"\|Height accuracy z (95 % confidence)
	\|style="background:WhiteSmoke; color:black"\|		\|style="background:WhiteSmoke; color:black"\|
	~ 2 % for a 1 µm step with the smallest measurement range and ~ 1 % for a 25 µm step "for well-defined steps that are easy to measure"		~ 2 % for a 1 µm step with the smallest measurement range and ~ 1 % for a 25 µm step ''for well-defined steps that are easy to measure.'' [[Specific Process Knowledge/Characterization/Stylus Profiler Measurement Uncertainty\|More info here]]
	\|-		\|-
	\|style="background:LightGrey; color:black"\|Max scan depth as a function of trench width W		\|style="background:LightGrey; color:black"\|Max scan depth as a function of trench width W

Reet at 11:11, 7 July 2025

2025-07-07T11:11:10Z

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	\|}		\|}

	~~==Measurement Accuracy==~~
	~~The accuracy of a height measurement with the profiler depends on the measurement settings, the sample, the instrument calibration and the resolution.~~

	~~===Adjust Measurement Settings for your Sample===~~
	Both the force setting and the scan speed are important: Too high force may compress a soft material like Al, Au or some polymers, while too low force may lead to the stylus "jumping" over features, especially if the scan speed is high. Too low scan speed may result in drift of the measurement and noise from vibrations while too high scan speed may mean that the stylus tip does not have time to reach the bottom of the features you are measuring and can also give rise to increased noise levels (see the [http://labmanager.dtu.dk/d4Show.php?id=2346&mach=304 Dektak XTA manual] on LabManager, Figure 3 for details).

	A sharp vertical step is easiest to measure. If the step is gradual or the surface is rough, it can be difficult to determine where to measure and how the scan should be leveled. Underlying sample curvature can also make it hard to level the scan.
	~~<br>~~
	~~<br>~~

	~~===Influence of Calibration Standard Uncertainty===~~
	[[File:intrinsic step h error.png\|350px\|upright=2\|alt=Axes with Measured values versus expected values and three lines illustrating measured=expected, plus two not-quite straight lines illustrating the confidence intervals growing as the values grow constrained by the calibration standard measurements. Two diamonds illustrate the location of the calibration sample measurement points. The plot's title says "Error from intrinsic uncertainty step height used for calibration".\|right\|thumb\|Figure 1: Measurement uncertainty from uncertainty in the calibration standard (Not to scale). The linearity of the sensor means that the measurement error increases approximately linearly with the size of the feature being measured. The percentage-wise error on the smallest standard step is larger than on the bigger standard step, meaning the lines are not completely straight.]]

	Nanolab staff check the instrument's measurement accuracy with a standard step height of 917 nm for the smaller ranges and 24.925 µm for the larger ranges, so that the middle ranges are checked with both standards. The 95 % confidence intervals for the standards are 17 nm for the 917 nm standard and 0.072 µm for the 24.925 µm standard. If the control measurement is beyond the limit set in our Quality Control procedure, the instrument is calibrated and the users informed (see LabManager for details, for instance the Dektak XTA [http://labmanager.dtu.dk/d4Show.php?id=2493&mach=304 control instruction] and [https://labmanager.dtu.dk/view_binary.php?type=data&mach=304 control measurement data])

	All this means that the 95 % confidence interval of a 1 µm step measured with the smallest measurement range is at least the 1.8 % error of the standard step while the 95 % confidence interval of a 25 µm step measured with a larger range is at least the 0.3 % error of the standard step. Steps between 1 and 25 µm measured with the intermediate ranges will presumably have an intermediate error ''just due to the intrinsic uncertainty on the standard step height''. See Figure 1.
	~~<br clear="all" />~~
	~~<br>~~

	~~===Total Uncertainty===~~
	[[File:Error probability distributions rev.png\|upright=2\|400px\|alt=Four different probability distributions that contribute to the total error on measurements with the Dektak XTA 6.5 micron range. By far the widest distribution is the one from the error on the standard step, which is a Gaussian. The others are the non-Gaussian spread of the average measurement of the standard height, which cuts off at the QC limits, the resolution, which is a very narrow uniform distribution, and the spread of measurement values for a given step being measured, which is a Gaussian whose width depends on the step in question.\|right\|thumb\|Figure 2: The probability distributions of the main sources of error that are convoluted to create the total error on a profiler measurement.]]

	Apart from the error due to the standard step height's intrinsic uncertainty, there will be a contribution to the overall uncertainty from the deviation of the value that the profiler measures from the theoretical height of the standard step that could be called "QC error" (since we accept some variation in our quality control routine). In practice for the 917 nm standard this range is about ± 4 nm for the Dektak XTA and ± 8 nm for the P17, while for the large standard it ranges from about 0.06 µm on the Dektak XTA to about 0.15 µm on the P17.

	There is also a tiny contribution to the total error from the instrument's limited resolution and finally of course there is random noise in any measurement. For many repeated measurements of the same line on the standard step height (a rigid, well defined vertical step) we have found the random error from the Dektak XTA is on the order of ± 5 nm for the 917 nm standard and 0.05 µm for the 24.925 µm standard. The random error with the P17 profiler is even smaller.

	To estimate the overall accuracy of the profiler's measurements you can convolute these various sources of error. The error sources are shown graphically in Figure 2 for measuring the small standard step with the Dektak XTA's smallest range. You can see an uncertainty budget for the Dektak XTA measurements here (''made by Rebecca Ettlinger''): [[Media:Uncertainty budget Dektak rev.xlsx \|Uncertainty budget Dektak rev.xlsx]]. It is based on the assumption that all the error sources are independent and can therefore be added by the sum of squares method.

	The resulting error calculation for the Dektak XTA of a 1 µm very well defined standard step is about 2 % (as the uncertainty on the calibration standard dominates), while for a very well defined step of 25 µm the cumulative error is about 0.7-1 %. However, in real devices the random error will often be much larger than for our standard samples and so the real confidence interval will be larger.

	To calculate the accuracy of your particular measurement, you should repeat the measurement several times and estimate the standard deviation. If the scatter is quite small you can try to calculate the total error on your measurement using the sum of squares method to combine the intrinsic step height error, the QC error and the random scatter error. If the scatter of your measurements is large that will be the dominant source of error in your measurement and you can safely ignore the other contributions.

	~~<br clear="all" />~~

Reet at 11:10, 7 July 2025

2025-07-07T11:10:04Z

← Older revision		Revision as of 13:10, 7 July 2025
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	The user manual, quality control procedure and results, technical information and contact information can be found in [http://labmanager.danchip.dtu.dk/function.php?module=Machine&view=view&mach=304 '''LabManager'''].		The user manual, quality control procedure and results, technical information and contact information can be found in [http://labmanager.danchip.dtu.dk/function.php?module=Machine&view=view&mach=304 '''LabManager'''].
	<br>		<br>

			Information on measurement accuracy and reproducibility for the stylus profilers may be found [[Specific Process Knowledge/Characterization/Stylus Profiler Measurement Uncertainty\|here]]
	<br>		<br>
	==Performance and Process Parameters==		==Performance and Process Parameters==
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	\|style="background:WhiteSmoke; color:black"\|		\|style="background:WhiteSmoke; color:black"\|
	*All materials that do not stick to the tip or leave residues on the chuck		*All materials that do not stick to the tip or leave residues on the chuck
	*For very soft polymers we recommend the Dektak 150~~, see below~~		*For very soft polymers we recommend the [[Specific Process Knowledge/Characterization/Topographic measurement#Comparison of Stylus Profilers, Optical Profilers and AFMs at Nanolab\| Dektak 150]].
	\|-		\|-
	\|}		\|}

Reet: /* Adjust Measurement Settings for your Sample */

2025-07-07T10:55:45Z

Adjust Measurement Settings for your Sample

← Older revision		Revision as of 12:55, 7 July 2025
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	===Adjust Measurement Settings for your Sample===		===Adjust Measurement Settings for your Sample===
	Both the force setting and the scan speed are important: Too high force may compress a soft material like Al, Au or some polymers, while too low force may lead to the stylus "jumping" over features, especially if the scan speed is high. Too low scan speed may result in drift of the measurement and noise from vibrations while too high scan speed may mean that the stylus tip does not have time to reach the bottom of the features you are measuring and can also give rise to increased noise levels (see the [http://labmanager.dtu.dk/d4Show.php?id=2346&mach=304 Dektak XTA manual] on ~~labmanager~~, Figure 3 for details).		Both the force setting and the scan speed are important: Too high force may compress a soft material like Al, Au or some polymers, while too low force may lead to the stylus "jumping" over features, especially if the scan speed is high. Too low scan speed may result in drift of the measurement and noise from vibrations while too high scan speed may mean that the stylus tip does not have time to reach the bottom of the features you are measuring and can also give rise to increased noise levels (see the [http://labmanager.dtu.dk/d4Show.php?id=2346&mach=304 Dektak XTA manual] on LabManager, Figure 3 for details).

	A sharp vertical step is easiest to measure. If the step is gradual or the surface is rough, it can be difficult to determine where to measure and how the scan should be leveled. Underlying sample curvature can also make it hard to level the scan.		A sharp vertical step is easiest to measure. If the step is gradual or the surface is rough, it can be difficult to determine where to measure and how the scan should be leveled. Underlying sample curvature can also make it hard to level the scan.

Reet at 08:58, 25 June 2025

2025-06-25T08:58:15Z

← Older revision		Revision as of 10:58, 25 June 2025
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	The Dektak XTA stylus profiler from Brüker is used for profiling surfaces of samples with structures in the micro- and nanometer range. The size of the structures that can be measured is limited by the tip dimensions.		The Dektak XTA stylus profiler from Brüker is used for profiling surfaces of samples with structures in the micro- and nanometer range. The size of the structures that can be measured is limited by the tip dimensions.

	A profile measurement can be done across a specific structure by using a high magnification camera to locate the structure. It is also possible to program the stylus to measure in several positions, defined with respect to some deskew points. [[Specific_Process_Knowledge/Characterization/Stress_measurement\|Stress measurements]] of thin films can be done by measuring the wafer bow. However, for predefined measurement programs or stress measurements, we recommend the P17 profiler ~~- see next section~~.		A profile measurement can be done across a specific structure by using a high magnification camera to locate the structure. It is also possible to program the stylus to measure in several positions, defined with respect to some deskew points. [[Specific_Process_Knowledge/Characterization/Stress_measurement\|Stress measurements]] of thin films can be done by measuring the wafer bow. However, for predefined measurement programs or stress measurements, we recommend the [[Specific_Process_Knowledge/Characterization/Tencor_P17\|P17 profiler]].

Reet at 08:54, 25 June 2025

2025-06-25T08:54:30Z

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	{{cc-nanolab}}		{{cc-nanolab}}

	'''Feedback to this page''': '''[mailto:labadviser@nanolab.dtu.dk?Subject=Feed%20back%20from%20page%20http://labadviser.nanolab.dtu.dk/index.php/Specific_Process_Knowledge/Characterization/~~Dektak XTA~~ click here]'''		'''Feedback to this page''': '''[mailto:labadviser@nanolab.dtu.dk?Subject=Feed%20back%20from%20page%20http://labadviser.nanolab.dtu.dk/index.php/Specific_Process_Knowledge/Characterization/Dektak_XTA click here]'''
	[[Category: Equipment\|Characterization Profiler]]		[[Category: Equipment\|Characterization Profiler]]
	[[Category: Characterization\|Profiler]]		[[Category: Characterization\|Profiler]]

Mmat: /* Dektak XTA Stylus Profiler */

2025-05-27T19:51:07Z

Dektak XTA Stylus Profiler

← Older revision		Revision as of 21:51, 27 May 2025
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	[[Category: Characterization\|Profiler]]		[[Category: Characterization\|Profiler]]

	=Dektak XTA Stylus Profiler=		=Dektak XTA (Stylus Profiler)=

	The Dektak XTA stylus profiler from Brüker is used for profiling surfaces of samples with structures in the micro- and nanometer range. The size of the structures that can be measured is limited by the tip dimensions.		The Dektak XTA stylus profiler from Brüker is used for profiling surfaces of samples with structures in the micro- and nanometer range. The size of the structures that can be measured is limited by the tip dimensions.

← Older revision		Revision as of 13:16, 7 July 2025
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	\|style="background:LightGrey; color:black"\|Scan range x y		\|style="background:LightGrey; color:black"\|Scan range x y
	\|style="background:WhiteSmoke; color:black"\|		\|style="background:WhiteSmoke; color:black"\|
	Line scan x: 50 µm to 55 mm in a single scan~~, up~~ to 200 mm with stiching		* Line scan: 50 µm to 55 mm in a single scan
			* Up to 200 mm with stiching
	\|-		\|-
	\|style="background:LightGrey; color:black"\|Scan range z		\|style="background:LightGrey; color:black"\|Scan range z
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	\|style="background:LightGrey; color:black"\|Resolution x y		\|style="background:LightGrey; color:black"\|Resolution x y
	\|style="background:WhiteSmoke; color:black"\|		\|style="background:WhiteSmoke; color:black"\|
	Down to 0.003 µm theoretically, in practice limited by ~~the~~ tip radius		Down to 0.003 µm theoretically, in practice limited by tip radius
	\|-		\|-
	\|style="background:LightGrey; color:black"\|Resolution z		\|style="background:LightGrey; color:black"\|Resolution z
	\|style="background:WhiteSmoke; color:black"\|		\|style="background:WhiteSmoke; color:black"\|
	1 Å, 10 Å, 80 Å or 160 Å (for ranges 65 kÅ, 655 kÅ, 5240 kÅ and 1 mm respectively)		1 Å, 10 Å, 80 Å or 160 Å for ranges 65 kÅ, 655 kÅ, 5240 kÅ and 1 mm respectively
	\|-		\|-
	\|style="background:LightGrey; color:black"\|Height accuracy z (95 % confidence)		\|style="background:LightGrey; color:black"\|Height accuracy z (95 % confidence)
	\|style="background:WhiteSmoke; color:black"\|		\|style="background:WhiteSmoke; color:black"\|
	~ 2 % for a 1 µm step with the ~~smallest measurement~~ range ~~and~~ ~ 1 % for a 25 µm step ''for well-defined steps that are easy to measure.'' [[Specific Process Knowledge/Characterization/Stylus Profiler Measurement Uncertainty\|More info here]]		*~ 2 % for a 1 µm step with the 65 kÅ range
			*~ 1 % for a 25 µm step
			*''for well-defined steps that are easy to measure.''
			*[[Specific Process Knowledge/Characterization/Stylus Profiler Measurement Uncertainty\|More info here]]
	\|-		\|-
	\|style="background:LightGrey; color:black"\|Max scan depth as a function of trench width W		\|style="background:LightGrey; color:black"\|Max scan depth as a function of trench width W
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	\| style="background:LightGrey; color:black"\|Substrate materials allowed		\| style="background:LightGrey; color:black"\|Substrate materials allowed
	\|style="background:WhiteSmoke; color:black"\|		\|style="background:WhiteSmoke; color:black"\|
	*All materials that do not stick to the tip or leave residues ~~on the chuck~~		*All materials that do not stick to the tip or leave residues
	*For very soft polymers we recommend the [[Specific Process Knowledge/Characterization/Topographic measurement#Comparison of Stylus Profilers, Optical Profilers and AFMs at Nanolab\| Dektak 150]].		*For very soft polymers we recommend the [[Specific Process Knowledge/Characterization/Topographic measurement#Comparison of Stylus Profilers, Optical Profilers and AFMs at Nanolab\| Dektak 150]].
	\|-		\|-
	\|}		\|}