Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials
The approaches for creating focused ion beams with a high current density and near-uniform current distribution in a spot, that allows an uniform dose for further micro irradiation technique, were considered. A numerical simulation of the microbeam formation was performed taking into account the eff...
Saved in:
| Date: | 2015 |
|---|---|
| Main Authors: | , , |
| Format: | Article |
| Language: | English |
| Published: |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2015
|
| Series: | Вопросы атомной науки и техники |
| Subjects: | |
| Online Access: | https://nasplib.isofts.kiev.ua/handle/123456789/112202 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Journal Title: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Cite this: | Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials / A.V. Romanenko, A.A. Ponomarov, A.G. Ponomarev // Вопросы атомной науки и техники. — 2015. — № 4. — С. 338-341. — Бібліогр.: 9 назв. — англ. |
Institution
Digital Library of Periodicals of National Academy of Sciences of Ukraine| id |
nasplib_isofts_kiev_ua-123456789-112202 |
|---|---|
| record_format |
dspace |
| spelling |
nasplib_isofts_kiev_ua-123456789-1122022025-02-09T22:19:24Z Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials Формування іонного мікрозондa для дослідження радіаційно-стимульованої сегрегації на границях зерен у конструкційних матеріалах Формирование ионного микрозонда для исследования радиационно-стимулированной сегрегации на границах зерен в конструкционных материалах Romanenko, A.V. Ponomarov, A.A. Ponomarev, A.G. Приложения и технологии The approaches for creating focused ion beams with a high current density and near-uniform current distribution in a spot, that allows an uniform dose for further micro irradiation technique, were considered. A numerical simulation of the microbeam formation was performed taking into account the effect of nonuniform distribution of the ion beam. The calculation method for a deconvolution of the beam brightness distribution parameters was improved. Experiments to verify theoretical calculations were performed. Розглянуто спосіб формування сфокусованого іонного пучка з великою густиною струму і з розподілом струму в плямі, що близький до рівномірного, з метою внесення рівномірної дози при мікроопроміненні. Проведено чисельні розрахунки з формування мікрозонда з урахуванням впливу нерівномірного розподілу іонів у пучку. Поліпшено чисельний метод, який дозволяє відновлювати параметри розподілу яскравості пучка. Проведено експериментальні роботи для верифікації теоретичних розрахунків. Рассмотрен способ формирования сфокусированного ионного пучка с высокой плотностью тока и с распределением тока в пятне, близким к равномерному, с целью внесения равномерной дозы при микрооблучении. Проведены численные расчеты по формированию микрозонда с учетом влияния неравномерного распределения ионов в пучке. Улучшен численный метод, позволяющий восстанавливать параметры распределения яркости пучка. Проведены экспериментальные работы для верификации теоретических расчетов. This work is performed with the support of the task program of scientific research of department of nuclear physics and energy of NAS of Ukraine “Development of perspective areas of fundamental research in nuclear, radiation physics and nuclear energy” (State egistration № 0111U10610). 2015 Article Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials / A.V. Romanenko, A.A. Ponomarov, A.G. Ponomarev // Вопросы атомной науки и техники. — 2015. — № 4. — С. 338-341. — Бібліогр.: 9 назв. — англ. 1562-6016 PACS: 29.17.-q https://nasplib.isofts.kiev.ua/handle/123456789/112202 en Вопросы атомной науки и техники application/pdf Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| language |
English |
| topic |
Приложения и технологии Приложения и технологии |
| spellingShingle |
Приложения и технологии Приложения и технологии Romanenko, A.V. Ponomarov, A.A. Ponomarev, A.G. Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials Вопросы атомной науки и техники |
| description |
The approaches for creating focused ion beams with a high current density and near-uniform current distribution in a spot, that allows an uniform dose for further micro irradiation technique, were considered. A numerical simulation of the microbeam formation was performed taking into account the effect of nonuniform distribution of the ion beam. The calculation method for a deconvolution of the beam brightness distribution parameters was improved. Experiments to verify theoretical calculations were performed. |
| format |
Article |
| author |
Romanenko, A.V. Ponomarov, A.A. Ponomarev, A.G. |
| author_facet |
Romanenko, A.V. Ponomarov, A.A. Ponomarev, A.G. |
| author_sort |
Romanenko, A.V. |
| title |
Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials |
| title_short |
Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials |
| title_full |
Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials |
| title_fullStr |
Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials |
| title_full_unstemmed |
Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials |
| title_sort |
ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2015 |
| topic_facet |
Приложения и технологии |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/112202 |
| citation_txt |
Ion microbeam formation for study of radiationinduced segregation at grain boundaries in construction materials / A.V. Romanenko, A.A. Ponomarov, A.G. Ponomarev // Вопросы атомной науки и техники. — 2015. — № 4. — С. 338-341. — Бібліогр.: 9 назв. — англ. |
| series |
Вопросы атомной науки и техники |
| work_keys_str_mv |
AT romanenkoav ionmicrobeamformationforstudyofradiationinducedsegregationatgrainboundariesinconstructionmaterials AT ponomarovaa ionmicrobeamformationforstudyofradiationinducedsegregationatgrainboundariesinconstructionmaterials AT ponomarevag ionmicrobeamformationforstudyofradiationinducedsegregationatgrainboundariesinconstructionmaterials AT romanenkoav formuvannâíonnogomíkrozondadlâdoslídžennâradíacíinostimulʹovanoísegregacíínagranicâhzerenukonstrukcíinihmateríalah AT ponomarovaa formuvannâíonnogomíkrozondadlâdoslídžennâradíacíinostimulʹovanoísegregacíínagranicâhzerenukonstrukcíinihmateríalah AT ponomarevag formuvannâíonnogomíkrozondadlâdoslídžennâradíacíinostimulʹovanoísegregacíínagranicâhzerenukonstrukcíinihmateríalah AT romanenkoav formirovanieionnogomikrozondadlâissledovaniâradiacionnostimulirovannoisegregaciinagranicahzerenvkonstrukcionnyhmaterialah AT ponomarovaa formirovanieionnogomikrozondadlâissledovaniâradiacionnostimulirovannoisegregaciinagranicahzerenvkonstrukcionnyhmaterialah AT ponomarevag formirovanieionnogomikrozondadlâissledovaniâradiacionnostimulirovannoisegregaciinagranicahzerenvkonstrukcionnyhmaterialah |
| first_indexed |
2025-12-01T08:38:21Z |
| last_indexed |
2025-12-01T08:38:21Z |
| _version_ |
1850294458308886528 |
| fulltext |
ISSN 1562-6016. ВАНТ. 2015. №4(98) 338
ION MICROBEAM FORMATION FOR STUDY OF RADIATION-
INDUCED SEGREGATION AT GRAIN BOUNDARIES IN
CONSTRUCTION MATERIALS
A.V. Romanenko, A.A. Ponomarov, A.G. Ponomarev
Institute of Applied Physics, National Academy of Sciences of Ukraine, Sumy, Ukraine
E-mail: romanenko@ipflab.sumy.ua
The approaches for creating focused ion beams with a high current density and near-uniform current distribution
in a spot, that allows an uniform dose for further micro irradiation technique, were considered. A numerical simula-
tion of the microbeam formation was performed taking into account the effect of nonuniform distribution of the ion
beam. The calculation method for a deconvolution of the beam brightness distribution parameters was improved.
Experiments to verify theoretical calculations were performed.
PACS: 29.17.-q
INTRODUCTION
Electrostatic accelerators are widely used in studies
of material behavior under strong irradiation damages
[1, 2]. Ion irradiation is highly relevant to simulate a
neutron irradiation [3]. The main advantage of the neu-
tron damage simulation by means of the ion irradiation
consists in a fast dose rate production (100 dpa in a few
hours for megaelectronvolt heavy ions). To decrease an
irradiation time it is necessary to increase a current den-
sity of ion beam. Focusing systems based on magnetic
quadrupole lenses (MQL) can increase the current den-
sity by three orders of magnitude [4]. Generally, a pro-
file of focused beam in the target plane has a Gaussian
shape [5]. Therefore, the scanning procedure is neces-
sary to get a region with a uniform dose distribution
over the entire area of irradiation that leads to a decrease
of effective dose of irradiation.
One of the tasks that require irradiation of mi-
croareas is an investigation of impurity segregation on
grain boundaries under irradiation (Fig. 1) [6]. Possibil-
ity to irradiate a single selected grain provides a study-
ing of segregation impurity and their moving along the
grain boundary from the irradiated grain to non-
irradiated one. Nuclear scanning microprobe is a unique
tool for carrying out such experiments. It provides ion
beams with high current density and permits to obtain a
map of element distribution using the micro-PIXE tech-
nique.
Fig. 1. Micrograph of type 304 austenitic stainless steel
[6], model of ion beam microirradiation
Constant environmental conditions (vacuum) during
irradiation and microanalysis, segregation formation
analysis depending on irradiation dose at the early stage
are ones of advantages of the nuclear microprobe appli-
cation for these tasks. Introduction of the uniform dose
is one of the main requirements for the irradiation.
Therefore, creating the focused ion beams with uniform
distribution in a spot is an actual problem that consists of
two tasks. The first one is to define a charged particles
distribution in the phase volume occupied by the beam at
the entrance to a probe forming system (PFS). The sec-
ond task is to find the conditions for beam formation on
the target with uniform current density distribution. The
present work is devoted to a solution of these tasks.
1. DECONVOLUTION OF THE BEAM
BRIGHTNESS DISTRIBUTION
PARAMETERS AT THE ENTRANCE
TO PROBE-FORMING SYSTEM
A method of the deconvolution of the beam bright-
ness distribution parameters at the entrance to PFS
based on the beam current distribution measurements
was described in details in [4]. It was used to study an
effect of a beam particles distribution on the microprobe
resolution. Proposed method is applied for obtaining the
brightness distribution in a small paraxial region. It as-
sumes an overlapping of independently movable slit
jaws of collimators relative to the geometrical axis,
when a displacement of jaws can take on a negative
value (the minimum values of -60 µm were used in
work [4] to study a central part of the beam with the
200×200 µm size). However, a conventional design of
the collimators doesn’t ensure the required overlapping
for measuring the overall beam region. Therefore, the
earlier developed method was modified in this work.
Fig. 2. Scheme of current beam distribution measure-
ment in the plane xOy at the microprobe channel
Measurements were carried out at the IAP’s
“SOKOL” electrostatic accelerator of the Van de Graaff
type for a 1 MeV proton beam [7]. Fig. 2 shows a sche-
ISSN 1562-6016. ВАНТ. 2015. №4(98) 339
matic arrangement of the object and angular collimators
for the beam current distribution measurements. Both
collimators are designed as two mutually perpendicular
slits. At first, the collimators were positioned with some
error with respect to the beam axis by measuring the
maximum current for the collimator window dimensions
of 100×100 µm. The direct current measurements were
performed using a current integrator.
The charged particles in most plasma ion sources
have Maxwellian velocity distribution. In this case the
particle phase density follows normal distribution.
Since ion sources and electrostatic accelerators are
axially symmetric, and the beam transportation optics
has a very low level of aberrations, the brightness distri-
bution in the four-dimensional phase space (x, y, x', y')
can be represented as a product of two distributions in
(x, x') and (y, y') planes
b(x, y, x´, y´) = b0·bx(x, x´)·by(y, y´), (1)
where
2
0
τ 2 2
τ τ
2
0 0 0
τ 2
τ
( )1( , ) exp
2(1 κ σ
( )( ) ( )2κ ;
σ σ σ
b
)
τ τ
τ ττ τ
τ τ τ τ τ τ
′ ′
−′ = − − −
′ ′ ′ ′− − −
− +
τ = (x, y); b0 is the axial brightness; τ0, τ′0 are the colli-
mator positioning errors; στ, στ′ are the standard devia-
tions; κτ is a correlation coefficient between τ and τ′; b0,
τ0 ,τ′0, στ, στ′, κτ, (τ = (x, y)) are the beam brightness dis-
tribution parameters deconvolved from beam current
measurements.
The beam current that passed through the object and
the angular collimators with the window dimensions
presented in Fig. 2 is
∫ ∫
−
−
⋅⋅⋅=Ω
i
i
j
j
x
x
AX
AX
xxxijx ddb
2
1
2
1
)μ(
)μ(
, μν)ν ,( α)( µa , (2)
where ax={αx, σx, x0, σ’x’, x’0, кx} is a vector of decon-
volved parameters of the beam brightness distribution in
the phase plane (x, x'); x1i, x2i are coordinates of the left
and right jaws of the vertical slit of the object collimator
respectively; Х1j, Х2j are coordinates of the left and right
jaws of the vertical slit of the angular collimator respec-
tively,
∫ ∫
−
−
−−
⋅⋅⋅=
y
y
y
y
r
r
AR
AR
yx ddbb
)(
)(
0 ),( α
µ
µ
µννµ is a normalization
factor, ry = 500 µm, Ry = 500 µm; ry are constant coordi-
nates of top and button jaws of the horizontal slit of the
object collimator; Ry are constant coordinates of top and
button jaws of the horizontal slit of the angular collima-
tor; A is the distance between the object and the angular
collimators; μ, ν are the integration parameters corre-
sponding to the linear and angular phase coordinates
respectively.
For measuring the current distribution in the y direc-
tion, one has to make the x↔y substitution in the ex-
pression (2). In relation (2) quantity Ωx,ij(аx) determines
a beam current passed through four-dimensional phase
window which is predetermined by positions of the ob-
ject and angular collimator jaws. The parameters’ vector
аx is determined by Levenberg-Marquradt’s fitting
method as a result of misalignment minimization
∑
=
∆
Ω−
=
),(
1),(
2
,
,,2 )(
)(χ
xx NM
ji ijx
xijxijx
x
I a
a , (3)
where аx is the parameters’ vector corresponded to the
minimum of function )(χ 2
xa ; Ix,ij is the measured value
of the beam current for a given four-dimensional phase
window which is predetermined by jaws’ positions x1i,
x2i, Х1j, Х2j, ry, Ry; Δx,ij is an error of the beam current
measurement; Mx, Nx are numbers of window variations
of the object and angular collimators.
After the distribution parameters σx, x0, σx’, x’0, кx, σy,
y0, σy’, y’0, кy were determined, the value of the axial
brightness for each of the four-dimensional phase win-
dow was defined by the relations
.),(
),(
,),(
),(
)μ(
)μ(
)μ(
)μ(
,,0
)μ(
)μ(
)μ(
)μ(
,,0
2
1
2
1
2
1
2
1
⋅⋅×
×⋅⋅=
⋅⋅×
×⋅⋅=
∫ ∫
∫ ∫
∫ ∫
∫ ∫
−
−
+−
−
+
−
−
+−
−
+
x
x
x
x
i
i
j
j
y
y
y
y
i
i
j
j
r
r
AR
AR
x
y
y
AY
AY
yijyijy
r
r
AR
AR
y
x
x
AX
AX
xijxijx
ddb
ddbIb
ddb
ddbIb
µννµ
µννµ
µννµ
µννµ
(4)
The beam current in the electrostatic accelerator has
temporal and spatial instability. The current instability
of "SOKOL" accelerator is at the level of 16%. There-
fore, the axial brightness is determined with an error in
the form of
rmsbbb 000 ∆±= , (5)
where 0b is an average brightness value for the sum of
window sizes calculated according to (4), Δb0rms is the
standard deviation.
At the beginning, the maximum value of coordinates
of the slit jaws was set at the level of 500 μm, i.e. the
sizes of the both collimators were 1 mm. Then, the sizes
of the object collimator x11=500, x21=0 were set, and the
current was measured at the every step of size changing
of angular collimator slits. The slit step size was
200 μm. The set was as follows: X11=500 X21=0;
X12=300 X22=0; X13=100 X23=100; X14=0 X24=300; X15=0
X25=500. After that the slit size of the object collimator
was changed by 200 μm and the current was measured
for the same set of angular collimator. The size set for
the object collimator was similar one as for the angular
collimator. Thus, at the end of the measurements we
have obtained the current’s matrix with dimension of
Mx=5, Nx=5. A similar procedure was carried out for
horizontal slits.
The obtained results are:
b0=(6.7±1.1) pA/(μm2·mrad2); σх = 621 μm; хo = -49 μm;
σх′ = 0.088 mrad; х′o = -0.016 mrad; κx = -0.4;
σy = 667 μm; yo = -11 μm; σy′ = 0.098 mrad;
y′o = 0.001 mrad; κy = -0.9.
ISSN 1562-6016. ВАНТ. 2015. №4(98) 340
2. BEAM FOCUSING SIMULATION
Formation of beams with a near-rectangular profile
of current density distribution at the target is possible on
condition that the ratio IFWHM/I0 is not less than 90%,
where IFWHM is a current at a region of full width at half
maximum (FWHM) in the beam profile, I0 is the total
beam current at the target. Therefore, searching of ob-
ject and angular collimators sizes which provide
IFWHM/I0 > 90% condition was the aim of the calcula-
tions. Simulation is based on a method of transportation
107 particles randomly distributed in the initial phase
space [8]. In the present work we took into account the
nonuniform distribution of particles at the PFS entrance
(obtained in the previous section). The calculations were
performed for 1 MeV proton beam with the maximum
energy spread δmax=10-3. The focusing system is four
quadrupole lenses powered as a separated "Russian
quadruplet" and has demagnification factor of 23×23
and working distance of 24 cm. The total beam current
over the range from 10 to 100 nA at the target was con-
sidered. As a result, the values for collimators whereby
current density distribution is close to rectangular were
determined (Fig. 3).
Fig. 3. Current density distribution at the target.
Ratio IFWHM to I0 is 95%, I0 = 40 nA
The direct on-line measurement of distribution pro-
file is difficult to perform in practice. That is why we
analyzed it by registration of secondary electron emis-
sion (SEE) during scanning of semi-infinite plates in
two directions traverse to the beam (Fig. 5,a). In order
to analyze experimental results we had to compare them
with theoretical ones. A simple program code was used
to obtain a theoretical profile of SEE and to modulate a
scanning procedure of a semi-infinite plate edge with
specified current density distribution [9].
3. EXPERIMENTAL
The measurements were performed in a nuclear
scanning microprobe using a proton beam with the ion
energy 1 MeV. At the beginning, exact focusing of the
beam was performed by scanning the probe over a cali-
brated micrometric square copper mesh to obtain a
stigmatic focusing. In this case, beam profile was repre-
sented by Gaussian shape. The target was replaced by
two crossed blades. Scan was carried out in the square
region which includes crossing point of blades. A yield
of secondary electrons was registered by SEE detector.
Scheme of the experiment is represented in Fig. 4.
Fig. 5,a shows the SEE map of these blades. Bright col-
our of edges is caused by additional SEE from edges
(Fig. 6). Then we set up theoretical calculated values of
collimators to obtain a uniform distribution of the cur-
rent density at the target. At the final, the edges of
blades were scanned and values for SEE profiles were
obtained and compared to theoretical ones (Fig. 5,b,c).
Fig. 4. Scheme of the experimental scanning of two
crossed blades by 1 MeV focused proton beam. Dash
line shows the region that corresponds to Fig. 5,a
a
b
c
Fig. 5. Edges of the blades. а) SEE map. Lines show
scanning directions. Comparison of theoretical (solid
line) and experimental (dash line) SEE profiles for X (b)
and Y (c) directions. Beam current was 40 nA
As can be seen, theoretical and experimental SEE
profiles are in good agreement at their central part. The
difference at the beginning and at the end of the shapes
is caused by non-rectangular shape of the sample edges.
SEE profiles strongly depend on shape of the sample
(see Fig. 6).
ISSN 1562-6016. ВАНТ. 2015. №4(98) 341
Fig. 6. Effect of a sample edge on the SEE profile
for a beam with IFWHM/I0= 100%
For the better agreement on the sides it is necessary
to put into the program the exact shape of the sample
(with μm-level precision). Stray magnetic fields may
have also influenced the experimental results.
CONCLUSIONS
The method of reconstruction of the beam brightness
distribution in the object collimator plane was im-
proved. New modified method enables to measure beam
with maximum size which is only limited by the open-
ing size of collimators. This is very important taking
into account design of the collimators. This method al-
lows deconvolution of the beam brightness distribution
in full phase volume occupied by the beam.
Numerical simulations have shown feasibility of for-
mation of ion beams with current density distribution close
to rectangular. The performed experimental work con-
firmed the theoretical results. Some differences between
theoretical and experimental results are caused by differ-
ence between edges of the real sample and its model.
ACKNOWLEDGEMENTS
This work is performed with the support of the task
program of scientific research of department of nuclear
physics and energy of NAS of Ukraine “Development
of perspective areas of fundamental research in nuclear,
radiation physics and nuclear energy” (State registration
№ 0111U10610).
REFERENCES
1. I.M. Nekluydov, B.V. Boris, V.V. Gan, G.D. Tol-
stolutskay. Methodology of the radiation damage
simulation of the solar battery converters by electron
and proton accelerators // Problems of Atomic Sci-
ence and Technology. Series «Physics of Radiation
Effect and Radiation Materials Science» (83). 2003,
v. 3, p. 62-65.
2. .V. Permyakov, V.V. Mel’nichenko, V.V. Bryk,
V.N. Voyevodin, Yu.E. Kupriyanova. Facility for
modeling the interactions effects of neutrons fluxes
with materials of nuclear reactors // Problems of
Atomic Science and Technology. Series «Physics of
Radiation Effect and Radiation Materials Science»
(90). 2014, v. 2, p. 180-186.
3. C. Abromeit. Aspects of simulation of neutron dam-
age by ion irradiation // Journal of Nuclear Materi-
als. 1994, v. 216, p. 78-96.
4. A.A. Ponomarov, V.I. Miroshnichenko, A.G.
Ponomarev. Influence of the beam current density
distribution on the spatial resolution of a nuclear mi-
croprobe // Nucl. Instr. and Meth. in Phys. Res. B.
2009, v. 267, p. 2041-2045.
5. C.N.B. Udalagama, A.A. Bettiol, J.A. van Kan,
E.J. Teo, F. Watt. The rapid secondary electron im-
aging system of the proton beam writer at CIBA //
Nucl. Instr. and Meth. B. 2007, v. 260, p. 390-395.
6. Parag Ahmedabadi, V. Kain, K. Arora, I. Samajdar,
S.C. Sharma, P. Bhagwat. Radiation-induced segre-
gation in desensitized type 304 austenitic stainless
steel // Journal of Nuclear Materials. 2011, v. 416,
p. 335-344.
7. V.E. Storizhko, A.G. Ponomarev, V.A. Rebrov,
A.I. Chemeris, A.A. Drozdenko, A.B. Dudnik,
V.I. Miroshnichenko, N.A. Sayko, P.A. Pavlenko,
L.P. Peleshuk. The Sumy scanning nuclear micro-
probe: Design features and first tests // Nucl. Instr.
and Meth. in Phys. Res. B. 2007, v. 260, p. 49-54.
8. A.G. Ponomarev, V.I. Miroshnichenko, V.E. Storizhko.
Optimum collimator shape and maximum emittance
for submicron focusing of ion beams. Determination
of the probe-forming system resolution limit // Nucl.
Instr. and Meth. A. 2003, v. 506, p. 20-25.
9. D.V. Magilin, A.G. Ponomarev, V.A. Rebrov,
N.A. Sayko, K.I. Melnik, V.I. Miroshnichenko,
V.Y. Storizhko. Performance of the Sumy nuclear
microprobe with the integrated probe-forming sys-
tem // Nucl. Instr. and Meth. in Phys. Res. B. 2009,
v. 267, p. 2046-2049.
Article received 30.04.2015
ФОРМИРОВАНИЕ ИОННОГО МИКРОЗОНДА ДЛЯ ИССЛЕДОВАНИЯ РАДИАЦИОННО-
СТИМУЛИРОВАННОЙ СЕГРЕГАЦИИ НА ГРАНИЦАХ ЗЕРЕН В КОНСТРУКЦИОННЫХ МАТЕРИАЛАХ
А.В. Романенко, А.А. Пономарёв, А.Г. Пономарёв
Рассмотрен способ формирования сфокусированного ионного пучка с высокой плотностью тока и с распределением
тока в пятне, близким к равномерному, с целью внесения равномерной дозы при микрооблучении. Проведены числен-
ные расчеты по формированию микрозонда с учетом влияния неравномерного распределения ионов в пучке. Улучшен
численный метод, позволяющий восстанавливать параметры распределения яркости пучка. Проведены эксперименталь-
ные работы для верификации теоретических расчетов.
ФОРМУВАННЯ ІОННОГО МІКРОЗОНДA ДЛЯ ДОСЛІДЖЕННЯ РАДІАЦІЙНО-СТИМУЛЬОВАНОЇ
СЕГРЕГАЦІЇ НА ГРАНИЦЯХ ЗЕРЕН У КОНСТРУКЦІЙНИХ МАТЕРІАЛАХ
О.В. Романенко, А.О. Пономарьов, О.Г. Пономарьов
Розглянуто спосіб формування сфокусованого іонного пучка з великою густиною струму і з розподілом струму в
плямі, що близький до рівномірного, з метою внесення рівномірної дози при мікроопроміненні. Проведено чисельні
розрахунки з формування мікрозонда з урахуванням впливу нерівномірного розподілу іонів у пучку. Поліпшено чисель-
ний метод, який дозволяє відновлювати параметри розподілу яскравості пучка. Проведено експериментальні роботи для
верифікації теоретичних розрахунків.
http://vant.kipt.kharkov.ua/CONTENTS/CONTENTS_2014_2.html
http://vant.kipt.kharkov.ua/CONTENTS/CONTENTS_2014_2.html
http://vant.kipt.kharkov.ua/CONTENTS/CONTENTS_2014_2.html
http://vant.kipt.kharkov.ua/CONTENTS/CONTENTS_2014_2.html
INTRODUCTION
1. DECONVOLUTION OF THE BEAM BRIGHTNESS DISTRIBUTION PARAMETERS AT THE ENTRANCE TO PROBE-FORMING SYSTEM
2. BEAM FOCUSING SIMULATION
3. EXPERIMENTAL
CONCLUSIONS
ACKNOWLEDGEMENTS
REFERENCES
ФОРМИРОВАНИЕ ИОННОГО МИКРОЗОНДА ДЛЯ ИССЛЕДОВАНИЯ РАДИАЦИОННО-СТИМУЛИРОВАННОЙ СЕГРЕГАЦИИ НА ГРАНИЦАХ ЗЕРЕН В КОНСТРУКЦИОННЫХ МАТЕРИАЛАХ
ФОРМУВАННЯ ІОННОГО МІКРОЗОНДA ДЛЯ ДОСЛІДЖЕННЯ РАДІАЦІЙНО-СТИМУЛЬОВАНОЇ СЕГРЕГАЦІЇ НА ГРАНИЦЯХ ЗЕРЕН У КОНСТРУКЦІЙНИХ МАТЕРІАЛАХ
|