Specific Process Knowledge/Characterization/Sample preparation - Revision history

Mmat at 14:53, 21 May 2025

2025-05-21T14:53:01Z

← Older revision		Revision as of 16:53, 21 May 2025
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	~~<!--Checked for updates on 24/8-2021. ok/ jmli-->~~

	=Replica Molding for Sample Inspection=		=Replica Molding for Sample Inspection=
	''by Frederik Stöhr ~~@danchip~~, May 2015''		''by Frederik Stöhr, DTU Nanolab (former DTU Danchip), May 2015''

	==Introduction==		==Introduction==
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	* There is a dedicated lab for work with PDMS at DTU Nanotech (not sure where it is now 2019-06-26).		* There is a dedicated lab for work with PDMS at DTU Nanotech (not sure where it is now 2019-06-26).
	* Please be aware that it is not allowed to work with PDMS in its uncured state inside the cleanroom. The list of approved chemicals inside the cleanroom still holds.		* Please be aware that it is not allowed to work with PDMS in its uncured state inside the cleanroom. The list of approved chemicals inside the cleanroom still holds.
	* Details on ~~Danchip’s~~ experience with PDMS as a casting material may be found in [[http://www.sciencedirect.com/science/article/pii/S0167931714005322 3]] (please cite!). A detailed description for PDMS casting can be found in [[http://www.nature.com/nprot/journal/v5/n3/full/nprot.2009.234.html 2]] and practical information is given in [[http://www.elveflow.com/microfluidic-tutorials/soft-lithography-reviews-and-tutorials/introduction-in-soft-lithography/pdms-softlithography-replication/ 4]].		* Details on our experience with PDMS as a casting material may be found in [[http://www.sciencedirect.com/science/article/pii/S0167931714005322 3]] (please cite!). A detailed description for PDMS casting can be found in [[http://www.nature.com/nprot/journal/v5/n3/full/nprot.2009.234.html 2]] and practical information is given in [[http://www.elveflow.com/microfluidic-tutorials/soft-lithography-reviews-and-tutorials/introduction-in-soft-lithography/pdms-softlithography-replication/ 4]].
	* The most important steps for obtaining high quality casts are the thorough mixing of the two components of the PDMS Kit (Sylgard 184, Dow Corning) and the sufficient outgassing of the polymer prior and after pouring the polymer into the mould. The house vacuum may be too weak. For special demands, try to get hold of a separate pump like a HiCube Classic from Pfeiffer Vacuum [[http://www.sciencedirect.com/science/article/pii/S0167931708004656 5]] (there is one around at DTU Photonics or Danchip).		* The most important steps for obtaining high quality casts are the thorough mixing of the two components of the PDMS Kit (Sylgard 184, Dow Corning) and the sufficient outgassing of the polymer prior and after pouring the polymer into the mould. The house vacuum may be too weak. For special demands, try to get hold of a separate pump like a HiCube Classic from Pfeiffer Vacuum [[http://www.sciencedirect.com/science/article/pii/S0167931708004656 5]] (there is one around at DTU Photonics or DTU Nanolab (former DTU Danchip)).
	* The application of an anti-stiction coating, like FDTS, is necessary. It may be applied inside the cleanroom by the MVD. Contact the respective person.		* The application of an anti-stiction coating, like FDTS, is necessary. It may be applied inside the cleanroom by the MVD. Contact the respective person.
	* The mold may be reused upon casting without deterioration (try!)		* The mold may be reused upon casting without deterioration (try!)

Bghe at 12:08, 7 January 2025

2025-01-07T12:08:20Z

← Older revision		Revision as of 14:08, 7 January 2025
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	Negative replicas of micro- or nanostructures can be obtained by casting with PDMS. This can facilitate the characterization of the three dimensional shape, the texture, or the roughness of a given sample. It may circumvent the inabilities of probes (AFM tip, stylus) to approach a surface of e.g. a deep and narrow cavity. It may also circumvent limitations of the optical profiler regarding the maximum detectable slope or the sensitivity of the CCD when measuring strongly tapered or deep cavities. PDMS is a common material in microfabrication and has unique properties that allow replicating features in the single nanometer range [[http://pubs.acs.org/doi/abs/10.1021/nl048355u 1]].		Negative replicas of micro- or nanostructures can be obtained by casting with PDMS. This can facilitate the characterization of the three dimensional shape, the texture, or the roughness of a given sample. It may circumvent the inabilities of probes (AFM tip, stylus) to approach a surface of e.g. a deep and narrow cavity. It may also circumvent limitations of the optical profiler regarding the maximum detectable slope or the sensitivity of the CCD when measuring strongly tapered or deep cavities. PDMS is a common material in microfabrication and has unique properties that allow replicating features in the single nanometer range [[http://pubs.acs.org/doi/abs/10.1021/nl048355u 1]].

	* A simplified list of necessary steps is given below.		* A simplified list of necessary steps is given below
	* Please follow the safety and working rules of the individual lab the work is done in and consider the safety instructions given in [[http://www.nature.com/nprot/journal/v5/n3/full/nprot.2009.234.html 2]].		* Please follow the safety and working rules of the individual lab the work is done in and consider the safety instructions given in [[http://www.nature.com/nprot/journal/v5/n3/full/nprot.2009.234.html 2]].
	* There is a dedicated lab for work with PDMS at DTU Nanotech (not sure where it is now 2019-06-26).		* There is a dedicated lab for work with PDMS at DTU Nanotech (not sure where it is now 2019-06-26).

Jmli at 14:14, 24 August 2021

2021-08-24T14:14:51Z

← Older revision		Revision as of 16:14, 24 August 2021
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			<!--Checked for updates on 24/8-2021. ok/ jmli-->

	=Replica Molding for Sample Inspection=		=Replica Molding for Sample Inspection=
	''by Frederik Stöhr @danchip, May 2015''		''by Frederik Stöhr @danchip, May 2015''

Bghe: /* Introduction */

2019-06-26T06:25:13Z

Introduction

← Older revision		Revision as of 08:25, 26 June 2019
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	* A simplified list of necessary steps is given below.		* A simplified list of necessary steps is given below.
	* Please follow the safety and working rules of the individual lab the work is done in and consider the safety instructions given in [[http://www.nature.com/nprot/journal/v5/n3/full/nprot.2009.234.html 2]].		* Please follow the safety and working rules of the individual lab the work is done in and consider the safety instructions given in [[http://www.nature.com/nprot/journal/v5/n3/full/nprot.2009.234.html 2]].
	* There is a dedicated lab for work with PDMS at DTU Nanotech.		* There is a dedicated lab for work with PDMS at DTU Nanotech (not sure where it is now 2019-06-26).
	* Please be aware that it is not allowed to work with PDMS in its uncured state inside the cleanroom. The list of approved chemicals inside the cleanroom still holds.		* Please be aware that it is not allowed to work with PDMS in its uncured state inside the cleanroom. The list of approved chemicals inside the cleanroom still holds.
	* Details on Danchip’s experience with PDMS as a casting material may be found in [[http://www.sciencedirect.com/science/article/pii/S0167931714005322 3]] (please cite!). A detailed description for PDMS casting can be found in [[http://www.nature.com/nprot/journal/v5/n3/full/nprot.2009.234.html 2]] and practical information is given in [[http://www.elveflow.com/microfluidic-tutorials/soft-lithography-reviews-and-tutorials/introduction-in-soft-lithography/pdms-softlithography-replication/ 4]].		* Details on Danchip’s experience with PDMS as a casting material may be found in [[http://www.sciencedirect.com/science/article/pii/S0167931714005322 3]] (please cite!). A detailed description for PDMS casting can be found in [[http://www.nature.com/nprot/journal/v5/n3/full/nprot.2009.234.html 2]] and practical information is given in [[http://www.elveflow.com/microfluidic-tutorials/soft-lithography-reviews-and-tutorials/introduction-in-soft-lithography/pdms-softlithography-replication/ 4]].

Bghe at 06:33, 29 June 2017

2017-06-29T06:33:55Z

← Older revision		Revision as of 08:33, 29 June 2017
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	<br clear="all" />		<br clear="all" />


	==Example: Replica Molding of cross sections of DRIE etched cavities==		==Example: Replica Molding of cross sections of DRIE etched cavities==

Bghe: /* Replica Molding for Sample Inspection */

2015-05-13T11:12:09Z

Replica Molding for Sample Inspection

← Older revision		Revision as of 13:12, 13 May 2015
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	=Replica Molding for Sample Inspection=		=Replica Molding for Sample Inspection=
	''by Frederik Stöhr @danchip''		''by Frederik Stöhr @danchip, May 2015''

	==Introduction==		==Introduction==

Frsto: /* Example: Replica Molding of cross sections of DRIE etched cavities */

2015-05-12T18:23:55Z

Example: Replica Molding of cross sections of DRIE etched cavities

← Older revision		Revision as of 20:23, 12 May 2015
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	]]		]]
	![[image:StackedSlices_3.jpg\|300x300px\|thumb\|left\|		![[image:StackedSlices_3.jpg\|300x300px\|thumb\|left\|
	Close up. The DRIE etched cavities are visible.		Close up. The DRIE etched cavities are visible. The edges of the slices are almost in one plane, allowing nice casting.
	]]		]]
	![[image:StackedSlicesWithFrame.jpg\|300x300px\|thumb\|left\|		![[image:StackedSlicesWithFrame.jpg\|300x300px\|thumb\|left\|

Frsto: /* Example: Replica Molding of cross sections of DRIE etched cavities */

2015-05-12T18:22:16Z

Example: Replica Molding of cross sections of DRIE etched cavities

← Older revision		Revision as of 20:22, 12 May 2015
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	{\| border="1" cellspacing="1" cellpadding="1" align="middle"		{\| border="1" cellspacing="1" cellpadding="1" align="middle"
	![[image:StackedSlices_2.jpg\|300x300px\|thumb\|left\|		![[image:StackedSlices_2.jpg\|300x300px\|thumb\|left\|
	Photograph of a multitude of silicon slices stacked and fixed with a purpose made clamp made of Aluminum.		Photograph of a multitude of silicon slices stacked and fixed with a purpose made clamp made of Aluminum. Attention must be payed to the straightness of the slices and the proper stacking of them, so they can be casted nicely.
	]]		]]
	![[image:StackedSlices_3.jpg\|300x300px\|thumb\|left\|		![[image:StackedSlices_3.jpg\|300x300px\|thumb\|left\|

Frsto: /* Example: Replica Molding of cross sections of DRIE etched cavities */

2015-05-12T18:19:34Z

Example: Replica Molding of cross sections of DRIE etched cavities

← Older revision		Revision as of 20:19, 12 May 2015
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	'''General Description'''<br>		'''General Description'''<br>
	As exemplified in [[http://www.sciencedirect.com/science/article/pii/S0167931714005322 3]] the three-dimensional shape of deep reactive ion etched cavities have been characterized by replica molding and atomic force microscopy (please cite!). Neither AFM directly, nor the optical profiler was able to do the job due to reasons explained above. The procedure proofed to be extremely reliable and accurate.		As exemplified in [[http://www.sciencedirect.com/science/article/pii/S0167931714005322 3]] the three-dimensional shape of deep reactive ion etched cavities in silicon have been characterized by replica molding and atomic force microscopy (please cite!). Neither AFM directly, nor the optical profiler was able to do the job due to reasons explained above. The procedure proofed to be extremely reliable and accurate.

	{\| border="1" cellspacing="1" cellpadding="1" align="middle"		{\| border="1" cellspacing="1" cellpadding="1" align="middle"

Frsto at 18:19, 12 May 2015

2015-05-12T18:19:04Z

← Older revision		Revision as of 20:19, 12 May 2015
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	'''General Description'''<br>		'''General Description'''<br>
	:~~Process date: Feb 2014<br>~~		As exemplified in [[http://www.sciencedirect.com/science/article/pii/S0167931714005322 3]] the three-dimensional shape of deep reactive ion etched cavities have been characterized by replica molding and atomic force microscopy (please cite!). Neither AFM directly, nor the optical profiler was able to do the job due to reasons explained above. The procedure proofed to be extremely reliable and accurate.
	~~:Recipe: m_res_ny@0degrees<br>~~
	~~:Process time: 5:30 min<br>~~
	~~:Substrate: 525 µm Si + 1~~.~~1 µm thermal silicon oxide + HMDS~~ (~~adhesion promoter~~) ~~<br>~~
	~~:Mask: [XOP3] AZ positive resist 1~~.~~5 µm thick (6-inch aligner 3 sec exposure~~, ~~60 sec developer)<br>~~
	~~:Etch Load (Total Exposed SiO2): ~ 10 %<br>~~
	~~:Post process: O2 Plasma Ashing 10 min~~
	{\| border="1" cellspacing="1" cellpadding="1" align="middle"		{\| border="1" cellspacing="1" cellpadding="1" align="middle"
	![[image:SEM_SliceCrossection_1.jpg\|300x300px\|thumb\|left\|		![[image:SEM_SliceCrossection_1.jpg\|300x300px\|thumb\|left\|