Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects
Thermal conductivity of single-crystal boron-doped diamonds (BDD) with ~ 2∙10¹⁹ cm⁻³ (~ 120 ppm) and 5∙10¹⁹ cm⁻³ (~ 300 ppm) boron content was studied by a steady-state method in a temperature range of 20–400. K. The obtained data were analyzed within Callaway model framework. The values of dislocat...
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Інститут надтвердих матеріалів ім. В.М. Бакуля НАН України
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| Cite this: | Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects / D. Prikhodko, S. Tarelkin, V. Bormashov, A. Golovanov, M. Kuznetsov, D. Teteruk, N. Kornilov, A. Volkov, A. Buga // Надтверді матеріали. — 2019. — № 1 (237). — С. 33-41. — Бібліогр.: 14 назв. — англ. |
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Prikhodko, D. Tarelkin, S. Bormashov, V. Golovanov, A. Kuznetsov, M. Teteruk, D. Kornilov, N. Volkov, A. Buga, A. 2020-03-23T13:05:05Z 2020-03-23T13:05:05Z 2019 Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects / D. Prikhodko, S. Tarelkin, V. Bormashov, A. Golovanov, M. Kuznetsov, D. Teteruk, N. Kornilov, A. Volkov, A. Buga // Надтверді матеріали. — 2019. — № 1 (237). — С. 33-41. — Бібліогр.: 14 назв. — англ. 0203-3119 https://nasplib.isofts.kiev.ua/handle/123456789/167288 21.921.34:661.65:537.31 Thermal conductivity of single-crystal boron-doped diamonds (BDD) with ~ 2∙10¹⁹ cm⁻³ (~ 120 ppm) and 5∙10¹⁹ cm⁻³ (~ 300 ppm) boron content was studied by a steady-state method in a temperature range of 20–400. K. The obtained data were analyzed within Callaway model framework. The values of dislocation density obtained from best fit of experimental data and from density of etch pits measuring were compared. Their discrepancy suggests presence of some other boron-related defects in crystal lattice. Теплопровідність монокристала, легованого бору (BDD) із вмістом бору ~ 2∙10¹⁹ cм⁻³ (~ 120 ppm) та 5∙10¹⁹ cм⁻³ (~ 300 ppm), було вивчено прийнятим методом в температурному діапазоні 20–400 К. Результати було проаналізовано в рамках моделі Каллавэй. Отримані значення щільності дислокацій добре узгоджуються з експериментальними даними і збігаються зі щільністю яскравих ямок травлення. Їх відмінність передбачає наявність деяких інших пов’язаних з бором дефектів в кристалічній решітці. Теплопроводность монокристалла, легированного бором (BDD) с содержанием бора ~ 2∙10¹⁹ cм⁻³ (~ 120 ppm) и 5∙10¹⁹ cм⁻³ (~ 300 ppm), была изучена принятым методом в температурном диапазоне 20–400 К. Полученные данные были проанализированы в рамках модели Каллавэй. Полученные значения плотности дислокаций хорошо согласовывались с экспериментальными данными и сравнивались с плотностью ямок травления. Их различие предполагает присутствие некоторых других связанных с бором дефектов в кристаллической решетке. This work was carried out using the facility of the Shared-Use Equipment Center of the Technological Institute for Superhard and Novel Carbon Materials supported by Ministry of Education and Science of Russian Federation within the agreement RFMEFI59317X0007 #14.593.21.007 en Інститут надтвердих матеріалів ім. В.М. Бакуля НАН України Сверхтвердые материалы Одержання, структура, властивості Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects Article published earlier |
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Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects |
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Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects Prikhodko, D. Tarelkin, S. Bormashov, V. Golovanov, A. Kuznetsov, M. Teteruk, D. Kornilov, N. Volkov, A. Buga, A. Одержання, структура, властивості |
| title_short |
Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects |
| title_full |
Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects |
| title_fullStr |
Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects |
| title_full_unstemmed |
Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects |
| title_sort |
low temperature thermal conductivity of heavily boron-doped synthetic diamond: influence of boron-related structure defects |
| author |
Prikhodko, D. Tarelkin, S. Bormashov, V. Golovanov, A. Kuznetsov, M. Teteruk, D. Kornilov, N. Volkov, A. Buga, A. |
| author_facet |
Prikhodko, D. Tarelkin, S. Bormashov, V. Golovanov, A. Kuznetsov, M. Teteruk, D. Kornilov, N. Volkov, A. Buga, A. |
| topic |
Одержання, структура, властивості |
| topic_facet |
Одержання, структура, властивості |
| publishDate |
2019 |
| language |
English |
| container_title |
Сверхтвердые материалы |
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Інститут надтвердих матеріалів ім. В.М. Бакуля НАН України |
| format |
Article |
| description |
Thermal conductivity of single-crystal boron-doped diamonds (BDD) with ~ 2∙10¹⁹ cm⁻³ (~ 120 ppm) and 5∙10¹⁹ cm⁻³ (~ 300 ppm) boron content was studied by a steady-state method in a temperature range of 20–400. K. The obtained data were analyzed within Callaway model framework. The values of dislocation density obtained from best fit of experimental data and from density of etch pits measuring were compared. Their discrepancy suggests presence of some other boron-related defects in crystal lattice.
Теплопровідність монокристала, легованого бору (BDD) із вмістом бору ~ 2∙10¹⁹ cм⁻³ (~ 120 ppm) та 5∙10¹⁹ cм⁻³ (~ 300 ppm), було вивчено прийнятим методом в температурному діапазоні 20–400 К. Результати було проаналізовано в рамках моделі Каллавэй. Отримані значення щільності дислокацій добре узгоджуються з експериментальними даними і збігаються зі щільністю яскравих ямок травлення. Їх відмінність передбачає наявність деяких інших пов’язаних з бором дефектів в кристалічній решітці.
Теплопроводность монокристалла, легированного бором (BDD) с содержанием бора ~ 2∙10¹⁹ cм⁻³ (~ 120 ppm) и 5∙10¹⁹ cм⁻³ (~ 300 ppm), была изучена принятым методом в температурном диапазоне 20–400 К. Полученные данные были проанализированы в рамках модели Каллавэй. Полученные значения плотности дислокаций хорошо согласовывались с экспериментальными данными и сравнивались с плотностью ямок травления. Их различие предполагает присутствие некоторых других связанных с бором дефектов в кристаллической решетке.
|
| issn |
0203-3119 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/167288 |
| citation_txt |
Low temperature thermal conductivity of heavily boron-doped synthetic diamond: Influence of boron-related structure defects / D. Prikhodko, S. Tarelkin, V. Bormashov, A. Golovanov, M. Kuznetsov, D. Teteruk, N. Kornilov, A. Volkov, A. Buga // Надтверді матеріали. — 2019. — № 1 (237). — С. 33-41. — Бібліогр.: 14 назв. — англ. |
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2025-11-25T23:29:45Z |
| last_indexed |
2025-11-25T23:29:45Z |
| _version_ |
1850581694008000512 |
| fulltext |
ISSN 0203-3119. Надтверді матеріали, 2019, № 1 33
UDC 621.921.34:661.65:537.31
D. Prikhodko1, 2, *, S. Tarelkin1, 3, V. Bormashov1, 2, 4,
A. Golovanov1, 2, M. Kuznetsov1, D. Teteruk1, N. Kornilov1,
A. Volkov1, A. Buga1, 2
1Technological Institute for Superhard and Novel Carbon Materials,
Troitsk, Moscow, Russia
2Moscow Institute of Physics and Technology,
Moscow Region, Russia
3National University of Science and Technology MISiS,
Moscow, Russia
4The All-Russian Research Institute for Optical
and Physical Measurements (VNIIOFI), Moscow, Russia
*dmprikhodko@gmail.com
Low temperature thermal conductivity
of heavily boron-doped synthetic diamond:
Influence of boron-related structure defects
Thermal conductivity of single-crystal boron-doped diamonds (BDD)
with ∼ 2⋅1019 cm–3 (∼ 120 ppm) and 5⋅1019 cm–3 (∼ 300 ppm) boron content was studied
by a steady-state method in a temperature range of 20–400. K. The obtained data were
analyzed within Callaway model framework. The values of dislocation density obtained
from best fit of experimental data and from density of etch pits measuring were
compared. Their discrepancy suggests presence of some other boron-related defects in
crystal lattice.
Keywords: boron-doped diamond; thermal conductivity; HPHT;
dislocation density.
INTRODUCTION
Diamond is known as the best thermal conductor. In [1–4]
temperature dependencies of thermal conductivity of pure single crystal diamonds
were measured and analyzed within the frameworks of Debye and Callaway
models. The dominating role of phonon scattering on isotope 13C atoms in thermal
conductivity reduction has been deduced. Studies [1–4] showed that the thermal
conductivity of diamond can be calculated using Callaway model [5] and the
model parameters for normal and umklapp processes have been evaluated.
However, the influence of different defects on thermal conductivity was not
analyzed.
Boron-doped IIb-type diamonds (BDD) are p-type semiconductors extensively
used in design of high-power, high-frequency, high temperature electronic devices
[6–8]. Thermal conductivity of single-crystal BDD is an important parameter for
electronic devices but it is much less investigated comparing to undoped IIa-type
diamonds. Recently we studied experimentally thermal conductivity of samples cut
from single-crystal BDD with ~ 5⋅1018 cm–3 boron content and from pure IIa-type
diamond in the temperature range of 20–400 K [9]. We found that extended defects
like dislocations have much stronger influence on thermal conductivity of BDD
© D. PRIKHODKO, S. TARELKIN, V. BORMASHOV, A. GOLOVANOV, M. KUZNETSOV, D. TETERUK,
N. KORNILOV, A. VOLKOV, A. BUGA, 2019
http://stmj.org.ua 34
than point defects. The parameters of Callaway model characterizing phonon
scattering on dislocations were estimated.
In the present work we studied thermal conductivity of two samples cut from
different single-crystal BDD with boron content higher than 1019 cm–3 in the same
temperature range. It is known that diamonds with boron content higher than
~ 4⋅1018 cm–3 have octahedral habitus instead of cubooctahedral one [10]. The
growth rate of (100) edge decreases substantially, thus the density of point and
extended defects may increase in a different way. In [9] BDD sample had
cubooctahedral habitus, while raw diamonds studied in this work have the
octahedral one.
EXPERIMENTAL DESIGN
We employed Physical Properties Measurement System™ (PPMS) by Quantum
Design with close cycle cryostat (EverCool-II) to achieve vacuum better than
10−5 Torr and high temperature accuracy and stability. The thermal conductivity
measurements were carried out by the steady-state method. This method is widely
used for thermal conductivity measurements. Its detailed description can be found
elsewhere [9, 10]. The design of the diamond sample for thermal conductivity
measurements is shown in Fig. 1.
Fig. 1. Design of the diamond sample for the steady-state method.
SAMPLES PREPARATION
We investigated synthetic single-crystal diamonds grown by the temperature
gradient method under high pressure and high temperature (HPHT) in a “toroid”
type high-pressure apparatus. 1.52 and 3.61 at % of amorphous boron powder was
added to the carbon source for IIb-type diamond growth. The resulted boron
content in the grown BDD crystals was ∼ 2⋅1019 cm–3 (∼ 120 ppm) and 5⋅1019 cm–3
(∼ 300 ppm). BDD crystal with 5⋅1019 cm–3 of boron is shown in Fig. 2, b.
Diamond sample with 2⋅1019 cm–3 boron had the same shape and color.
One can see that crystals in Figs. 2, a and 2, b have different habits. Such
change of habits consistently takes place when boron content exceeds 1019 cm–3.
More details of the growth process, electrical properties and heat capacity of sin-
ISSN 0203-3119. Надтверді матеріали, 2019, № 1 35
gle-crystal BDD were described in [11–13]. We used proprietary laser cut system
to prepare (001) plates from grown crystals, and then mechanically polished them.
The resulting thickness of plates was about 180 μm. X-ray topography images of
fabricated plates are shown in Fig. 3.
2 mm 2 mm
a b
Fig. 2. As-grown diamonds: ∼ 5⋅1018 (a) and ∼ 5⋅1019 (b) cm–3 of boron.
2 mm 2 mm
a b
Fig 3. X-ray diffraction topography of BDDs with 2⋅1019 (a) and 5⋅1019 (b) cm–3 of boron. Con-
tours of samples for thermal conductivity measurements are pointed out.
To ensure the electrical isolation between metallic contacts used for tempera-
ture sensors and heater the thin (∼ 10 μm) insulating layer of high pure diamond
was grown homoepitaxially on each plate in microwave plasma reactor by PLAS-
SYS. After proper treatment of the diamond plates surfaces three platinum resistors
of ∼ 1 kΩ resistance have been deposited using lift-off optical lithography and
magnetron sputtering (Fig. 4). They act as a resistive heater and two temperature
sensors for hot and cold sample edges.
Due to a very high thermal conductivity of diamond, we decided to decrease
sample cross-section and, therefore, increase heat pulse propagation time for more
reliable measurements. Thus, the sample geometry was modified by laser cutting to
create a narrow neck of 0.3 mm width and 2.7 and 4 mm length (for 300 and
120 ppm samples respectively). Contours of the finally cut samples and their
position with respect to the entire plates are shown in Fig. 3.
Commercial PPMS chuck was used for mounting of samples. It provides
electrical connections of sensors and the heater and acts as a thermal bath. The
http://stmj.org.ua 36
electrical leads were made using a conventional ultrasonic thermal-compression
welding (Fig. 5).
500 μm
Fig. 4. Electrical heater (top) and resistive temperature sensor (bottom) at the upper end of the
sample (before cut).
5 mm
Fig. 5. BDD sample installed on the sample holder.
EXPERIMENTAL RESULTS AND DISCUSSION
Measurement results collected on both boron-doped diamond samples are
presented in Fig. 7. The results for IIa diamond and BDD with 5⋅1018 cm–3 boron
content from [9] are shown for comparison.
It is clearly seen that the thermal conductivity decreases with the boron content
increase. At room temperature it drops from about 2300 W/(m·K) for IIa-type
diamond to about 500 W/(m·K) for BDD with 5⋅1019 cm–3 boron content. Unlike
IIa-type diamond and BDD with ∼ 5⋅1018 cm–3 boron, the thermal conductivity of
BDDs with 2⋅1019 cm–3 and 5⋅1019 cm–3 boron does not have evident maximum in a
low temperature range. At ∼ 100 K IIa-type diamond has thermal conductivity of
about 17000 W/(m·K), while sample with the highest boron content has thermal
conductivity about 250 W/(m·K), that is about 70 times less.
Following the results of our previous work, we focused on dislocations density
in new samples. We estimated the number of dislocations by counting the etch pits.
ISSN 0203-3119. Надтверді матеріали, 2019, № 1 37
To count etch pits we etched properly polished and cleaned diamond surface in
H2/O2 plasma for 10 minutes at ∼ 850 °C. We also etched BDD plate with
5⋅1018 cm–3 boron content to compare with more heavily doped crystals. The
images of etched surfaces are shown in Fig. 6.
50 μm 50 μm 50 μm
a b c
Fig. 6. Etched surfaces of diamonds with different boron content: ∼ 5⋅1018 (a), ∼ 2⋅1019 (b),
∼ 5⋅1019 (c) cm–3.
0 100 200 300 40010
1
10
2
10
3
10
4
4
3
2
T
he
rm
al
c
on
du
ct
iv
it
y,
W
/(
m
·K
)
T, K
1
Fig. 7. Measured and calculated thermal conductivity of diamond samples with different boron
content; experimental results: ▲ – IIa (from [9]); ● – 5⋅1018 cm–3 (from [9]); ■ – 2⋅1019 cm–3;
♦ – 5⋅1019 cm–3; theoretical calculation: 1 – IIa (from [9]); 2 – 5⋅1018 cm–3 (from [9]); 3 – 2⋅1019 cm–3;
4 – 5⋅1019 cm–3.
One can see that the dislocation densities in single-crystal BDDs with
2⋅1019 and 5⋅1019 cm–3 of boron are similar. It equals to ∼ 7⋅105 cm–2 which is
substantially less than ∼ 2⋅106 cm–2 in BDD with 5⋅1018 cm–3
boron content (see
Fig. 6, a).
X-ray topography (see Fig. 3) indicates that apart of the boundaries of growth
sectors the density of extended defects is not very high, but it is higher in more
heavily boron-doped sample.
Before applying Callaway model of thermal conductivity for semiconductors
one should estimate the contribution of electronic thermal conductivity. The
electrical conductivity of heavily boron-doped diamond is lower than 5 Ω·cm at
300 K and drops sharply at lower temperatures. Then, according to Wiedemann-
Franz law
mK
W
T
e
k
k B
e
3
2
1033 −⋅≈σ
= . (1)
http://stmj.org.ua 38
This estimation shows that electronic thermal conductivity is more than 5 orders
less than measured thermal conductivity. That means that in the case of boron-
doped diamond we can neglect the electronic contribution and consider only pho-
non thermal conductivity.
Callaway model was used to analyze experimental results in the same way it
was done in [9]. The total scattering time of acoustic phonons is given by
τ
=
τ i i
11
. (2)
Detailed description of different process of phonon scattering and expressions
for their characteristic scattering time can be found in [4], [10].
For normal processes [4]
π
ω=
τ 2
1 3AT
N
. (3)
Here A – temperature independent parameter; T – temperature; ω – phonon
frequency.
For umklapp processes [10]
T
C
U
D
TeB
θ−
−υλ=
τ
21
, (4)
B, C – temperature independent parameters; λ – phonon wavelength; υ – average
sound velocity in the material.
For boundary scattering [10]
db
υ=
τ
1
, (5)
d – parameter related to sample size.
Due to mass difference of host atoms and lattice deformations caused by
doping, phonon scattering time for point defects [10]:
1
4
2
3
2
0
2
3
0
2
4
1
−
ω
δ
πυ
+
δ
πυ
=
τ R
RVn
M
MV p
p
, (6)
M – atomic mass of the crystal; δM – difference between masses of substitutional
and host atoms; R, δR – radius of the host atom and difference between radiuses of
substitutional and host atoms; V0 – volume per atom; np – point defects density.
To take into account a phonon scattering on dislocations we need to consider
two main factors: scattering on irregularities within crystal and on elastic field
arose around them. In [10] the following expressions for scattering times are given:
3
2
4
1
1 ω
υ
=
τ
r
NK D
core
; (7)
ω
π
γ=
τ 2
1 22
2
D
D
str
B
NK , (8)
K1, K2 – temperature independent parameters; ND – dislocation density; BD – Bur-
gers vector of the dislocation; r – dislocation radius; γ – Gruneisen parameter.
ISSN 0203-3119. Надтверді матеріали, 2019, № 1 39
In the previous work we determined parameters A, B and C in (3) and (4) for IIa
diamond and IIb diamond with ∼ 5⋅1018 cm–3 boron content. From fitting the data
on BDD with 5⋅1018 cm–3 boron we determined parameters K1 and K2 in
expressions (7) and (8), which describe phonon-dislocation scattering. The values
of these parameters are given in the table.
Parameter
of the model
Process Value Reference
A Normal processes (Eq. 3) 1.9⋅10–11 K–3 [9]
B Umklapp processes (Eq. 4) 2.2⋅10–12 cm·K–1 [9]
C Umklapp processes (Eq. 4) 670 K [9]
K1 Dislocation core scattering (Eq. 7) 8.8⋅103 This work
K2 Elastic field scattering (Eq. 8) 9.6⋅105 This work
We estimated the dislocation density of BDDs with 2⋅1019 and 5⋅1019 cm–3 of
boron from the best fit with the model parameters from the table. The
corresponding graphs are shown in Fig. 8.
0 100 200 30010
1
10
2
10
3
10
4
5
4
3
2
1
T
he
rm
al
c
on
du
ct
iv
it
y,
W
/(
m
·K
)
T, K
a
0 100 200 30010
0
10
1
10
2
10
3
10
4
5
4
2
3
1
T
he
rm
al
c
on
du
ct
iv
it
y,
W
/(
m
·K
)
T, K
b
Fig. 8. Calculated impacts of different processes of phonon scattering on the total thermal con-
ductivity of single-crystal BDD with 2⋅1019 (a) and 5⋅1019 cm–3 (b) of boron: 1 – boundery scat-
tering; 2 – umklapp processes; 3 – boron atoms; 4 – isotopes (n(13C) = 1.1 %); 5 – dislocations;
6 – total thermal conductivity; ■ – experimental results.
http://stmj.org.ua 40
Each line (see Fig. 8) is the calculated thermal conductivity in a presence of
only one process of phonon scattering. Thus, the total thermal conductivity is
“lower than the lowest”.
The best fit of experimental data was achieved at dislocation densities of
∼ 3.7⋅106 and ∼ 3.6⋅107 cm–2 for BDDs with 2⋅1019 and 5⋅1019 cm–3 boron content
respectively. These values are more than an order of magnitude higher than the
ones measured by etch pits counting (see Fig. 7).
The real dislocation density may be underestimated using etch pits pictures if
screw dislocations with opposite screw orientation locate close each other and
compensate its elastic strain field. In this case, they do not provide etch pits but
phonons still can scatter on dislocation core.
Otherwise, if the dislocation density indeed does not increase with boron
content rise and change of the crystal habitus, some other defects must cause
thermal conductivity drop. That can be B–C and B–B pairs or some more
complicated defects. In [14] Polyakov et al. suggest the formation of B–C pairs
which further evaluate into plain B–C clusters called nanosheets. Such defects may
have greater scattering cross-section than single substitutional boron atom and
therefore affect the thermal conductivity stronger. Some fundamental conversion
may take place in BDD lattice defects structure with an increase of boron content
above ~ 5⋅1018 cm–3
and change of the grown crystal habitus. The thermal
conductivity of such BDDs may be explained within Callaway model framework if
new types of defects with other scattering times take part in phonon-defect
scattering.
CONCLUSIONS
We have grown single crystal boron-doped diamonds with boron content of
∼ 2⋅1019 and ∼ 5⋅1019 cm–3 and investigated their thermal conductivity in the
temperature range of 20–400 K. Generally, the thermal conductivity decreases with
boron content increase. We analyzed the obtained data within Callaway model
framework. Fitting the experimental data with theoretical curves gave the densities
of extended defects much higher than the values obtained by etch pits counting.
The densities of etch pits in more heavily boron-doped crystals is less than in the
crystal with 5⋅1018 cm–3 boron content. We suppose that either neighbor screw
dislocation of the opposite sign effectively reduce lattice tensions, thus the density
of etch pits reduces, or a new type of extended defects with the unknown phonon
scattering time appear. The change of the grown crystal habitus from
cubooctahedral to octahedral one at boron content above 5⋅1018 cm–3 may also be
associated with a change in the structure of lattice defects. The temperature
dependence of thermal conductivity of such BDDs may be described within
Callaway model framework if new types of defects with other scattering times take
part in phonon-defect scattering or if the density of etch pits is really substantially
less than the real density of extended defects.
ACKNOWLEDGEMENTS
This work was carried out using the facility of the Shared-Use Equipment
Center of the Technological Institute for Superhard and Novel Carbon Materials
supported by Ministry of Education and Science of Russian Federation within the
agreement RFMEFI59317X0007 #14.593.21.007
Теплопровідність монокристала, легованого бору (BDD) із вмістом бо-
ру ∼ 2⋅1019 cм–3 (∼ 120 ppm) та 5⋅1019 cм–3 (∼ 300 ppm), було вивчено прийнятим методом в
температурному діапазоні 20–400 К. Результати було проаналізовано в рамках моделі
ISSN 0203-3119. Надтверді матеріали, 2019, № 1 41
Каллавэй. Отримані значення щільності дислокацій добре узгоджуються з експеримента-
льними даними і збігаються зі щільністю яскравих ямок травлення. Їх відмінність перед-
бачає наявність деяких інших пов’язаних з бором дефектів в кристалічній решітці.
Ключові слова: алмаз, легований бором, теплопровідність, високий
тиск, висока температура, плотність дислокацій.
Теплопроводность монокристалла, легированного бором (BDD) с со-
держанием бора ∼ 2⋅1019 cм–3 (∼ 120 ppm) и 5⋅1019 cм–3 (∼ 300 ppm), была изучена приня-
тым методом в температурном диапазоне 20–400 К. Полученные данные были проанали-
зированы в рамках модели Каллавэй. Полученные значения плотности дислокаций хорошо
согласовывались с экспериментальными данными и сравнивались с плотностью ямок
травления. Их различие предполагает присутствие некоторых других связанных с бором
дефектов в кристаллической решетке.
Ключевые слова: алмаз, легированный бором, теплопроводность, высо-
кое давление, высокая температура, плотность дислокаций.
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Received 28.11.17
Revised 07.02.18
Accepted 12.02.18
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