High-density data recording via laser thermo-lithography and ion-beam etching
Pits 250 – 300 - nm wide were obtained on the surface of thin organic nanocomposite film using master-disc laser-burning station with 405 nm laser beam focused by 0.85 NA lens. The film with obtained pits was used as a mask for subsequent reactive ion-beam etching of glass substrate. Finally, 150...
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Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України
2014
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nasplib_isofts_kiev_ua-123456789-1183502025-02-23T20:11:31Z High-density data recording via laser thermo-lithography and ion-beam etching Gorbov, I.V. Kryuchyn, A.A. Grytsenko, K.P. Manko, D.Yu. Borodin, Yu.O. Pits 250 – 300 - nm wide were obtained on the surface of thin organic nanocomposite film using master-disc laser-burning station with 405 nm laser beam focused by 0.85 NA lens. The film with obtained pits was used as a mask for subsequent reactive ion-beam etching of glass substrate. Finally, 150 – 200-nm pits were performed on the substrate surface. Nanocomposite films were based on organic positive photoresist with a dye inclusions. This dye is characterized by wide absorption band within the spectral region 390–410 nm and can be evaporated by laser irradiation with the wavelength 405 nm 2014 Article High-density data recording via laser thermo-lithography and ion-beam etching / I.V. Gorbov, A.A. Kryuchyn, K.P. Grytsenko, D.Yu. Manko, Yu.O. Borodin // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2014. — Т. 17, № 1. — С. 52-55. — Бібліогр.: 7 назв. — англ. 1560-8034 PACS 81.16.Nd https://nasplib.isofts.kiev.ua/handle/123456789/118350 en Semiconductor Physics Quantum Electronics & Optoelectronics application/pdf Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України |
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Pits 250 – 300 - nm wide were obtained on the surface of thin organic
nanocomposite film using master-disc laser-burning station with 405 nm laser beam
focused by 0.85 NA lens. The film with obtained pits was used as a mask for subsequent
reactive ion-beam etching of glass substrate. Finally, 150 – 200-nm pits were performed
on the substrate surface. Nanocomposite films were based on organic positive photoresist
with a dye inclusions. This dye is characterized by wide absorption band within the
spectral region 390–410 nm and can be evaporated by laser irradiation with the
wavelength 405 nm |
| format |
Article |
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Gorbov, I.V. Kryuchyn, A.A. Grytsenko, K.P. Manko, D.Yu. Borodin, Yu.O. |
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Gorbov, I.V. Kryuchyn, A.A. Grytsenko, K.P. Manko, D.Yu. Borodin, Yu.O. High-density data recording via laser thermo-lithography and ion-beam etching Semiconductor Physics Quantum Electronics & Optoelectronics |
| author_facet |
Gorbov, I.V. Kryuchyn, A.A. Grytsenko, K.P. Manko, D.Yu. Borodin, Yu.O. |
| author_sort |
Gorbov, I.V. |
| title |
High-density data recording via laser thermo-lithography and ion-beam etching |
| title_short |
High-density data recording via laser thermo-lithography and ion-beam etching |
| title_full |
High-density data recording via laser thermo-lithography and ion-beam etching |
| title_fullStr |
High-density data recording via laser thermo-lithography and ion-beam etching |
| title_full_unstemmed |
High-density data recording via laser thermo-lithography and ion-beam etching |
| title_sort |
high-density data recording via laser thermo-lithography and ion-beam etching |
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Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України |
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2014 |
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https://nasplib.isofts.kiev.ua/handle/123456789/118350 |
| citation_txt |
High-density data recording via laser thermo-lithography
and ion-beam etching / I.V. Gorbov, A.A. Kryuchyn, K.P. Grytsenko, D.Yu. Manko, Yu.O. Borodin // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2014. — Т. 17, № 1. — С. 52-55. — Бібліогр.: 7 назв. — англ. |
| series |
Semiconductor Physics Quantum Electronics & Optoelectronics |
| work_keys_str_mv |
AT gorboviv highdensitydatarecordingvialaserthermolithographyandionbeametching AT kryuchynaa highdensitydatarecordingvialaserthermolithographyandionbeametching AT grytsenkokp highdensitydatarecordingvialaserthermolithographyandionbeametching AT mankodyu highdensitydatarecordingvialaserthermolithographyandionbeametching AT borodinyuo highdensitydatarecordingvialaserthermolithographyandionbeametching |
| first_indexed |
2025-11-24T23:40:21Z |
| last_indexed |
2025-11-24T23:40:21Z |
| _version_ |
1849717026812067840 |
| fulltext |
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2014. V. 17, N 1. P. 52-55.
© 2014, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
52
PACS 81.16.Nd
High-density data recording via laser thermo-lithography
and ion-beam etching
I.V. Gorbov1, A.A. Kryuchyn1, K.P. Grytsenko2, D.Yu. Manko1, Yu.O. Borodin1
1Institute for Information Recording of National Academy of Science of Ukraine
2, str. M. Shpaka, 03113, Kiev, Ukraine
2V. Lashkaryov Institute of Semiconductor Physics of NAS of Ukraine, 41, prospect Nauky, 03028 Kiev, Ukraine
Gorbov I.V.: tel.: (38-044) 454-22-19, fax: (38-044) 456-33-18, e-mail: ivan-gorbov@list.ru
Kryuchyn A.A.: tel.: (38-044) 454-21-52, fax: (38-044) 241-72-33, e-mail: ipri@ipri.kiev.ua
Grytsenko K.P.: tel.: (38-044) 525-55-30, e-mail: d.grytsenko@gmail.com
Manko D.Yu.: tel.: (38-044) 454-22-09, fax: (38-044) 456-33-18, e-mail: dmitriy.manko@gmail.com
Borodin Yu.O.: tel.: (38-044) 454-21-14, fax: (38-044) 456-33-18, e-mail: borodiny@yahoo.com
Abstract. Pits 250 – 300 - nm wide were obtained on the surface of thin organic
nanocomposite film using master-disc laser-burning station with 405 nm laser beam
focused by 0.85 NA lens. The film with obtained pits was used as a mask for subsequent
reactive ion-beam etching of glass substrate. Finally, 150 – 200-nm pits were performed
on the substrate surface. Nanocomposite films were based on organic positive photoresist
with a dye inclusions. This dye is characterized by wide absorption band within the
spectral region 390–410 nm and can be evaporated by laser irradiation with the
wavelength 405 nm.
Keywords: optical data recording, laser thermo-lithography, organic nanocomposite
films, ion-beam etching.
Manuscript received 11.12.13; revised version received 23.01.14; accepted for
publication 20.03.14; published online 31.03.14.
1. Introduction
A recognized advantage of optical storage is the low cost
mass-production of read-only-memory media [1].
Generally, optical data recording is the process where
one or several features of recording medium are
changing under the influence of focused laser radiation.
In conventional photochemical data recoding, all
irradiated media are exposed and changed. In this case,
the data recording density is restricted by the diffraction
limit. Using the Rayleigh criterion that is determined by
the relationship dmin = 0.61×λ/NA (where λ is the
wavelength, NA – numerical aperture, dmin – minimal
size of a pit), we can obtain that for λ = 405 nm,
NA = 0.85, dmin ~ 0.3m; and for λ = 375 nm,
NA = 0.95, dmin = 0.2 m.
To reach these sizes, we usually use photo-
chemical process that is widely used in optical disc
mastering. The process is described for recording and
reproducing information comprising the steps of
imagewise exposing the recording layer including a
polymeric composition that is photochemically
hardenable under actinic light and treating the exposed
layer with heat and/or a vapor containing solvent for the
said polymeric composition.
The development of optical data storage has
reached a stage when further progress along the classical
way of reducing the diffraction limit seems questionable.
In this sense, a parallel between optical data storage and
high-resolution lithography is evident. However,
because of the professional environment in which optical
lithography is used, exotic wavelengths like 193 nm
(KrF-laser) or even 13.5 nm (plasma-generated extreme
UV) are possible. Liquid immersion has also been
successfully applied in optical lithography to further
increase the capacity of integrated circuits [2]. These
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2014. V. 17, N 1. P. 52-55.
© 2014, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
53
technologies are expensive and complicate. In our
opinion, if a suitable organic dye material is available,
which provides high resolution similar to recording
materials used for writable optical disk, than it could be
possible to design high density optical disk with the
surface density close or more to Blu-ray disk.
Laser thermo-lithography, also known as phase-
transition mastering transforms an inorganic photoresist
layer from the initial state into a transformed state by
laser beam heating [3]. Recording pits can be reached by
removing the transformed areas with acid or alkaline
solutions. Furthermore, the sizes of recording pits can
overcome the diffraction limit, which allows the usage
of a visible laser beam as a light source and reduces the
cost of equipment [3].
At the same time, in high-density thermo-
lithography data recording, the relevant process takes
place only in the area where phase transition occurs. The
dimensions of the area can be significantly smaller than
the laser spot size, which makes it possible to increase
the density of optical recording. The goal of research
consists in creation of technology for high-density
recording on thin films of photosensitive nanocomposite
materials.
In this paper, we propose alternative method to
make high density optical discs, using the thermo-
lithography principle. In our proposal, we introduced a
fine structure in the recorded optical effects in such a
manner that more bits than one can be stored per
location.
2. Laser thermo-lithography data recording on
organic nanocomposite films
Thermo-lithography data recording requires using a
proper recording medium with predefined
characteristics. In this work, intra-ionic conjugated
systems (dyes) characterized by intensive and selective
absorption in the spectral region 390 – 410 nm were
elaborated. We used 3-styryl bases derivatives of
benzothiazole substituted at phenyl residue or at
chromophore; 4-nullmethinemerocyanines derivatives of
thiobarbitutric acid and 6-membered nitrogen- or
oxygen-containing heterocycles; one naphtostyryl
derivative dyes [4]. These dyes are able to be
evaporated by 405 nm laser radiation. The
nanocomposite films were created on base of organic
positive photoresist that is also sensitive to 405 nm
radiation and added synthesized dye with various
concentrations. The 150-nm layer of nanocomposite
film was deposited on glass substrates. The process in
accord with the high-density data recording method is
close to mastering the optical discs for long-term data
storage (Fig. 2) [5].
Fig. 2. Stages of the data recording process by laser thermo-
lithography and reactive ion-beam etching: 1 – nanocomposite
film, 2 – substrate, 3 – focused laser beam, 4 – pits in
nanocomposite films, 5 – ion beam.
Fig. 1 Schematic view of the intensity profile for a blue mastering spot (405 nm, NA=0.9) and the target BD-ROM pit width [3].
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2014. V. 17, N 1. P. 52-55.
© 2014, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
54
During the recording process, the nanocomposite
film layer was heated and particularly evaporated under
the influence of laser radiation. The concentration of
dye in the film defines intensity of light absorption and
temperature gradient within the layer. This gradient
should be as sharp as possible in order to get a
minimum characteristic size of obtained pits. Note that
pit profile is defined by decomposition temperature of
the film as well. Thermogravimetric analysis of several
nanocomposite films based on various organic dyes
with different decomposition temperature showed that
thermal properties of the film are mainly defined by
photoresist properties. The analysis showed that
decomposition temperature of photoresist is close to
540 ºC. The minimum pit width was reached using
organic dye with 270 ºC decomposition temperature
and 0.6 mass % concentration in the film.
In the result, the pits with 250 – 300-nm width
were obtained on the thin organic nanocomposite film
by using master-disc laser-burning station with 405-nm
laser beam focused with 0.85 NA lens. It should be
noted that conventional photochemical data recoding
on this laser-burning station allows obtaining only 500
– 550 nm pits widths [6]. Another difference of the
obtained pits is its tapered form with 50 – 100-nm
bottoms (Fig. 3). This allows to use the obtained pits as
a mask for subsequent reactive ion-beam etching
because the bottom size will defined final pits size.
a)
b)
Fig. 3. Nanocomposite film surface after recording (a) and
initial pit profile (b).
3. Final pit formation with ion-beam etching
For high-density data recording, it is necessary to apply
dry etching techniques based on sputtering the substrate
material atoms by high energy ions of gas-discharge
plasma [7]. Ion-beam etching has highest anisotropy
among these methods because material etching is
executed by directional bombardment by inert gas plasma
ions. In this case, the undercutting of structures sidewall is
insignificant. It allows creating nanostructures with 0.01
cross size accuracy of the structure depth.
Reactive ion-beam etching is used to increase the
etching rate and selectivity [7]. It is based on application
of reactive gases in contrast to the previous one. In this
case, the etching is based on reciprocally amplified
processes of impact interaction and chemical reactions
between plasma ions and work material atoms. It
sufficiently increases etch speed and selectivity, but
keeps a high level of anisotropy.
The nanocomposite film with obtained pits was used
as a mask for reactive ion-beam etching of soda-siliceous
glass substrate. Operating CF4 gas is usually used for
siliceous materials [7]. Then, we also use this gas for
reactive ion-beam etching of soda-siliceous glass substrate
surface. The 150 – 200-nm pits were obtained on the
substrate surface in the result of the etching (Fig. 4). The
size of obtained pits is close to that of Blu-ray format.
Then, the proposed method may be considered as an
alternative way to create master-discs for BD media.
a)
b)
Fig. 4. Substrate surface after ion-beam etching (a) and the
final pit profile (b).
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2014. V. 17, N 1. P. 52-55.
© 2014, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
55
4. Conclusions
Proposed nanocomposite organic films allows switching
data recoding process from conventional photochemical
to laser thermo-lithography that considerably decreased
pits sizes from 550 down to 300 nm. The proposed ion-
beam etching additionally decreased pit sizes down to
150 – 200 nm. The discussed laser thermo-lithography
method may be used as an alternative way to create
master-discs for Blu-ray media. The proposed method
may be used to fabricate high-density optical media for
long-term data storage as well.
References
1. E. Meinders, R. Rastogi, M. van der Verr, P. Peeters,
H. Majdoubi, H. Bulle, A. Millet, D. Bruls. Phase
transitions mastering of high-density optical media //
Japanese Journal of Applied Physics, 46 (6B),
p. 3987-3992 (2007).
2. A. van de Nes, J. Braat, S. Pereira. High-density
optical data storage // Reports on Progress in
Physics, 69, p. 2323-2363 (2006).
3. Jh. Chen, J. Lin, J. Chen, K. Chiu. Optimization of
Ge–Sb–Sn–O Films for Thermal Lithography of
Submicron Structures // Japanese Journal of Applied
Physics. 51, p. 06FC03-1 – 06FC03-6. DOI:
10.1143/JJAP.51.06FC03 (2012).
4. K. Grytsenko, O. Belyaev, A. Kryuchin, I. Gorbov,
S. Schrader, V. Ksianzou. Optical recording media
based on nanoparticles for superhigh density
information storage // Optical Memory and Neural
Networks, 22(3), p. 127-134 (2013).
5. V. Petrov, A. Kryuchyn, I. Gorbov. High-density
optical disks for long-term information storage //
Proc. SPIE 8011, 22nd Congress of the International
Commission for Optics: Light for the Development of
the World, 80112J, DOI: 10.1117/12.900745
(25 October 2011).
6. V.V. Petrov, A.A. Kryuchyn, S.M. Shanoylo, V.G.
Kravets, I.O. Kossko, E.V. Belyak, A.S. Lapchuk,
S.A. Kostyukevych Super-dense optical registrtation
of information – National Academy of Sciences of
Ukraine, Institute for Information Recording. – Kiev:
National Academy of Sciences of Ukraine, 2009.–
282 p.
7. V.V. Petrov, A.A. Kryuchyn, I.V. Gorbov. Using
ion beams for crea-tion of nanostructures on the
surface of high-stable materials // Semiconductor
Physics, Quantum Electronics & Optoelectronics,
10(1), p. 27-29 (2007).
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2014. V. 17, N 1. P. 52-55.
PACS 81.16.Nd
High-density data recording via laser thermo-lithography
and ion-beam etching
I.V. Gorbov1, A.A. Kryuchyn1, K.P. Grytsenko2, D.Yu. Manko1, Yu.O. Borodin1
1Institute for Information Recording of National Academy of Science of Ukraine
2, str. M. Shpaka, 03113, Kiev, Ukraine
2V. Lashkaryov Institute of Semiconductor Physics of NAS of Ukraine, 41, prospect Nauky, 03028 Kiev, Ukraine
Gorbov I.V.: tel.: (38-044) 454-22-19, fax: (38-044) 456-33-18, e-mail: ivan-gorbov@list.ru
Kryuchyn A.A.: tel.: (38-044) 454-21-52, fax: (38-044) 241-72-33, e-mail: ipri@ipri.kiev.ua
Grytsenko K.P.: tel.: (38-044) 525-55-30, e-mail: d.grytsenko@gmail.com
Manko D.Yu.: tel.: (38-044) 454-22-09, fax: (38-044) 456-33-18, e-mail: dmitriy.manko@gmail.com
Borodin Yu.O.: tel.: (38-044) 454-21-14, fax: (38-044) 456-33-18, e-mail: borodiny@yahoo.com
Abstract. Pits 250 – 300 - nm wide were obtained on the surface of thin organic nanocomposite film using master-disc laser-burning station with 405 nm laser beam focused by 0.85 NA lens. The film with obtained pits was used as a mask for subsequent reactive ion-beam etching of glass substrate. Finally, 150 – 200-nm pits were performed on the substrate surface. Nanocomposite films were based on organic positive photoresist with a dye inclusions. This dye is characterized by wide absorption band within the spectral region 390–410 nm and can be evaporated by laser irradiation with the wavelength 405 nm.
Keywords: optical data recording, laser thermo-lithography, organic nanocomposite films, ion-beam etching.
Manuscript received 11.12.13; revised version received 23.01.14; accepted for publication 20.03.14; published online 31.03.14.
1. Introduction
A recognized advantage of optical storage is the low cost mass-production of read-only-memory media [1]. Generally, optical data recording is the process where one or several features of recording medium are changing under the influence of focused laser radiation. In conventional photochemical data recoding, all irradiated media are exposed and changed. In this case, the data recording density is restricted by the diffraction limit. Using the Rayleigh criterion that is determined by the relationship dmin = 0.61×λ/NA (where λ is the wavelength, NA – numerical aperture, dmin – minimal size of a pit), we can obtain that for λ = 405 nm, NA = 0.85, dmin ~ 0.3(m; and for λ = 375 nm, NA = 0.95, dmin = 0.2 (m.
To reach these sizes, we usually use photo-chemical process that is widely used in optical disc mastering. The process is described for recording and reproducing information comprising the steps of imagewise exposing the recording layer including a polymeric composition that is photochemically hardenable under actinic light and treating the exposed layer with heat and/or a vapor containing solvent for the said polymeric composition.
The development of optical data storage has reached a stage when further progress along the classical way of reducing the diffraction limit seems questionable. In this sense, a parallel between optical data storage and high-resolution lithography is evident. However, because of the professional environment in which optical lithography is used, exotic wavelengths like 193 nm (KrF-laser) or even 13.5 nm (plasma-generated extreme UV) are possible. Liquid immersion has also been successfully applied in optical lithography to further increase the capacity of integrated circuits [2]. These technologies are expensive and complicate. In our opinion, if a suitable organic dye material is available, which provides high resolution similar to recording materials used for writable optical disk, than it could be possible to design high density optical disk with the surface density close or more to Blu-ray disk.
Laser thermo-lithography, also known as phase-transition mastering transforms an inorganic photoresist layer from the initial state into a transformed state by laser beam heating [3]. Recording pits can be reached by removing the transformed areas with acid or alkaline solutions. Furthermore, the sizes of recording pits can overcome the diffraction limit, which allows the usage of a visible laser beam as a light source and reduces the cost of equipment [3].
At the same time, in high-density thermo-lithography data recording, the relevant process takes place only in the area where phase transition occurs. The dimensions of the area can be significantly smaller than the laser spot size, which makes it possible to increase the density of optical recording. The goal of research consists in creation of technology for high-density recording on thin films of photosensitive nanocomposite materials.
In this paper, we propose alternative method to make high density optical discs, using the thermo-lithography principle. In our proposal, we introduced a fine structure in the recorded optical effects in such a manner that more bits than one can be stored per location.
2. Laser thermo-lithography data recording on organic nanocomposite films
Thermo-lithography data recording requires using a proper recording medium with predefined characteristics. In this work, intra-ionic conjugated systems (dyes) characterized by intensive and selective absorption in the spectral region 390 – 410 nm were elaborated. We used 3-styryl bases derivatives of benzothiazole substituted at phenyl residue or at chromophore; 4-nullmethinemerocyanines derivatives of thiobarbitutric acid and 6-membered nitrogen- or oxygen-containing heterocycles; one naphtostyryl derivative dyes [4]. These dyes are able to be evaporated by 405 nm laser radiation. The nanocomposite films were created on base of organic positive photoresist that is also sensitive to 405 nm radiation and added synthesized dye with various concentrations. The 150-nm layer of nanocomposite film was deposited on glass substrates. The process in accord with the high-density data recording method is close to mastering the optical discs for long-term data storage (Fig. 2) [5].
Fig. 2. Stages of the data recording process by laser thermo-lithography and reactive ion-beam etching: 1 – nanocomposite film, 2 – substrate, 3 – focused laser beam, 4 – pits in nanocomposite films, 5 – ion beam.
During the recording process, the nanocomposite film layer was heated and particularly evaporated under the influence of laser radiation. The concentration of dye in the film defines intensity of light absorption and temperature gradient within the layer. This gradient should be as sharp as possible in order to get a minimum characteristic size of obtained pits. Note that pit profile is defined by decomposition temperature of the film as well. Thermogravimetric analysis of several nanocomposite films based on various organic dyes with different decomposition temperature showed that thermal properties of the film are mainly defined by photoresist properties. The analysis showed that decomposition temperature of photoresist is close to 540 ºC. The minimum pit width was reached using organic dye with 270 ºC decomposition temperature and 0.6 mass % concentration in the film.
In the result, the pits with 250 – 300-nm width were obtained on the thin organic nanocomposite film by using master-disc laser-burning station with 405-nm laser beam focused with 0.85 NA lens. It should be noted that conventional photochemical data recoding on this laser-burning station allows obtaining only 500 – 550 nm pits widths [6]. Another difference of the obtained pits is its tapered form with 50 – 100-nm bottoms (Fig. 3). This allows to use the obtained pits as a mask for subsequent reactive ion-beam etching because the bottom size will defined final pits size.
a)
b)
Fig. 3. Nanocomposite film surface after recording (a) and initial pit profile (b).
3. Final pit formation with ion-beam etching
For high-density data recording, it is necessary to apply dry etching techniques based on sputtering the substrate material atoms by high energy ions of gas-discharge plasma [7]. Ion-beam etching has highest anisotropy among these methods because material etching is executed by directional bombardment by inert gas plasma ions. In this case, the undercutting of structures sidewall is insignificant. It allows creating nanostructures with 0.01 cross size accuracy of the structure depth.
Reactive ion-beam etching is used to increase the etching rate and selectivity [7]. It is based on application of reactive gases in contrast to the previous one. In this case, the etching is based on reciprocally amplified processes of impact interaction and chemical reactions between plasma ions and work material atoms. It sufficiently increases etch speed and selectivity, but keeps a high level of anisotropy.
The nanocomposite film with obtained pits was used as a mask for reactive ion-beam etching of soda-siliceous glass substrate. Operating CF4 gas is usually used for siliceous materials [7]. Then, we also use this gas for reactive ion-beam etching of soda-siliceous glass substrate surface. The 150 – 200-nm pits were obtained on the substrate surface in the result of the etching (Fig. 4). The size of obtained pits is close to that of Blu-ray format. Then, the proposed method may be considered as an alternative way to create master-discs for BD media.
a)
b)
Fig. 4. Substrate surface after ion-beam etching (a) and the final pit profile (b).
4. Conclusions
Proposed nanocomposite organic films allows switching data recoding process from conventional photochemical to laser thermo-lithography that considerably decreased pits sizes from 550 down to 300 nm. The proposed ion-beam etching additionally decreased pit sizes down to 150 – 200 nm. The discussed laser thermo-lithography method may be used as an alternative way to create master-discs for Blu-ray media. The proposed method may be used to fabricate high-density optical media for long-term data storage as well.
References
1. E. Meinders, R. Rastogi, M. van der Verr, P. Peeters, H. Majdoubi, H. Bulle, A. Millet, D. Bruls. Phase transitions mastering of high-density optical media // Japanese Journal of Applied Physics, 46 (6B), p. 3987-3992 (2007).
2. A. van de Nes, J. Braat, S. Pereira. High-density optical data storage // Reports on Progress in Physics, 69, p. 2323-2363 (2006).
3. Jh. Chen, J. Lin, J. Chen, K. Chiu. Optimization of Ge–Sb–Sn–O Films for Thermal Lithography of
Submicron Structures // Japanese Journal of Applied Physics. 51, p. 06FC03-1 – 06FC03-6. DOI: 10.1143/JJAP.51.06FC03 (2012).
4. K. Grytsenko, O. Belyaev, A. Kryuchin, I. Gorbov, S. Schrader, V. Ksianzou. Optical recording media based on nanoparticles for superhigh density information storage // Optical Memory and Neural Networks, 22(3), p. 127-134 (2013).
5. V. Petrov, A. Kryuchyn, I. Gorbov. High-density optical disks for long-term information storage // Proc. SPIE 8011, 22nd Congress of the International Commission for Optics: Light for the Development of the World, 80112J, DOI: 10.1117/12.900745 (25 October 2011).
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Fig. 1 Schematic view of the intensity profile for a blue mastering spot (405 nm, NA=0.9) and the target BD-ROM pit width [3].
© 2014, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
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