SCIENTIFIC ABSTRACT YEFIMOV, YE. A. - YEFIMOV, YU. V.

• Document Type: CREST
• Collection: Scientific Abstracts
• Document Number (FOIA) /ESDN (CREST): CIA-RDP86-00513R001962410007-1
• Release Decision: RIF
• Original Classification: S
• Document Page Count: 100
• Document Creation Date: November 2, 2016
• Document Release Date: September 19, 2001
• Sequence Number: 7
• Publication Date: December 31, 1967
• Content Type: SCIENTIFIC ABSTRACT

SOY/2o-126-1- 33/58
On Particular Features of Electrolytic Oxidation Reactions on ~ Germanium
Anode
(referred to normal hydrogen electrode) on the currenl density
of an n- and p-germanium anode with a specific resistivity
of 1.5 ohm-cm and a diffusion length of 0-4 - 0-5 mm. The
introduction of potassium oxalate into the solutions decreases
the potential of n-germanium, This phenomenon is particular-
ly marked in the case of high current densities at which,,
for the anodic dissolution of the n-Ge the limiting c-arren't
of the diffusion of the holes occurs. By the addition of
the oxalate ion this limiting current vanishes. The oxida-
tion of the oxalaie, which occurs simultaneously with the
dissolution of the Ge, increases the latter within the poten-
tial range, in which it is otherwise limited by diffusion
of the holes to the surface of the semiconductor. The im-
'pression is conveyed that the anodic oxidation of
C 02- increases the concentration of the holes on the surface
2 4
and thus facilitates dissolution, This is explained by the
authors by the fact that the oxidation of the oxalate ion
is not due to the holea but to the penetration of electrons
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SOV/20--128-1-33/58
On Particular Features of Electrolytic Oxidation Reactioa8 on a Ge-rManium
Anode
into the Ge-anode. In the case of p-Ge the lowering of the
potential by oxidation of the oxalate ion occurs only at low
current densities. If curr;nt densities are higher, an anodic
dissolution of Ge, which is not influenced by the presence
of the C 02- occurs. In a similar manner the oxidation of
2 4
KJ (Fig 2) develope. Ifere a further process is added, which
accelerates the anodic dissolution of Ce, viz. the reduction
of J on'the anode by the capture of electrons from the
valence zone. This reduction could also be visually confirmed
because the discoloring of the solution, which is character-
istic of iodine, did not occur. Iodine in this case probably
plays the part of a current carrier and promotes the exchange
of electrons between the valence zone and the zone of con-
ductivity. Herefrom the authors draw the folloving conclu-
sions: Only the reaction of the anodic dissolution of Germanium,
which is connected with the destruction of the crystal lattice,
is limited by the diffusion of the holes to the surface.
Other oxidation reactions davelop without the assistance of
Card 3/4 the holes, but by the penetration of electrons into the anode.
There are 2 figures and 8 references, 4 of which are Soviet.

5/076/60/034/012/017/027
,B02OJBO67
AUTHORS: Yefimov, Ye. A. and Yerusalimchik, lo Go, Moscow
TITLE: Hydrogen Evolution on a Germanium Cathode
PERIODICAL: Zhurnal fizioheskoy khimii, 1960, Vol. 34v Ho. 12,
pp. 2804-2807
TEXT: In contrast to the results obtained by W. Brattain and C. Garrett
(Re 1) the authors found no difference in the course of the polarization
curv;B (il-logI) which were taken on p- and n-type germanium at current
densities of 1o-5 to 1o-1 a/cm2 after previous long-lasting polarization
(Ref. 2). The authors attempted to study the reasons of the rbeence of
a distinct electron diffusion boundary current on the polarization curves.
The curves potential - current were taken by a quick method which permitted
the polarization measurements to be made at a low hydrogen overvoltage. In
the experiments the voltage was applied to the electrolyzer by a special
generator of sawtooth_pulses which allowed the voltage supply to be
changed from 30 to lo 4 see. The potential of the germanium electrode
was measured in 0.1 N HC1 at current densities of jo-3 to 3.10-2 a/cm2
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Hydrogen Evolution on a Germanium Cathode S/076j6C)/034/012/017/027
B020/BO67
and 200 as referred to a hydrogen electrode in the same solution (Fig. 1).
Curve 1 corresponds to n-type germanium and curve 2 to p-type germanium.
The curves were taken within three seconds. At a potential more negative
than 0.6 v the curves I - I for n- and p-type germanium cathodes diverge.
At I - 3-10- 2 a/cM2 the polarization of the p-type germanium electrode
increases by 0.3 v compared to that of n-type germanium. When measuring
the potential after preceding cathodic polarization of the electrode to
a constant potential no deviation was found between the curves of p-type
and n-type germanium. The difference in the kinetics of the electrolytic
evolution of hydrogen on p- and n3type sermanium becomes manifest only at
current densities exceeding 3.10- a/cm and in a very short initial
range. This phenomenon is connected with the bending of the energy zones
on the semiconductor surface during adsorption and the entrance of the
hydrogen atoms into the cryiital lattice. Fig. 2 shows the y - I curves for
a solution of 0.1 N HC1 + 0.1 N (NH4)2S 208which were taken within three
seconds on n-(curve 1) and p-(curve 2) type germanium, whereas curve 3
corresponds to the hydrogen evolution in20 1 N HCl on n-type germanium.
At current densities exceeding 10-1 a/am ;he potential of the p- and
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Hydrogen Evolution on a Germanium Cathode 3/076/60/034/012/017/027
B020/BO67
n-type germanium electrode rose strongly and anomalously (Fig. 3). This
was not the case in degenerate semiconductors because of their ohmic fall
of potential in the impoverished layer on the germanium surface and in.
the semiconductor mass. The electron diffusion from the mass of p-type
germanium to its surface reduces the rate of electrochemical reaction
neither in hydrogen evolution nor in the reduction of the peraullato ion.
There are 3 fiaurcz and ref'eronccn: "5 Sovl(!L, (1";, tird British,
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4
3
~67 116 0 0
SOY120-111 -2-31/69
0
AUTHORSt Yefimov, Ye. A., Yerusalimchik, L G~,
TITLEs On the Particular Features of the Electrochemical Dissolu-
tion of n-Type Silicon t~
PERIODICAL; Doklady Akademii nauk SSSR, 1960, Vol 130, Nr 2,
PP 353 - 355 (USSR)
ABSTRAM This paper is an experimental confirmation of the assump-
tion made by J.Flynn (Ref ~), ao cording to which, un-
like what is the case with germaniiimq mainly the holes
are used up in the electrochemical 'isoolution of Si which
are formed in the space charge layer on the boundary between
semiconductor and electrolytev and where only an insigni-
ficant number of holes is formed by generation within the
semiconductor. The method employed is described in refer-
ence 3. The experiments were made by means of an a-silicon
lamella (resistivity about 3 ohmo*cm), On one side of the
lamella a p-n junction with an area of 0,03 GIM2 was pro-
duced by melting aluminum, and an the same side an Qhmic
contact was connected. The lamells. was insulated by means
Card 1/3 of silicon-varnish and paraffin with the exception of the
ISM

3
0n the Particular Features of the Electrochemical SOV/20-130-2-51/6~
Dissolution of n-Type Silicon
place opposite the p-n junction-The thickness of the
n-Si layer between the boundary of the p-region and the
electrolyte was 20-251t- The experiments were made at
200 in 2.5n IIF. Figure 1 shows the polarization curves of
the anodic dissolution of ^i in the interval of current
densities from 10-6 to 5.10-4 a/cm2. Curve I was obtained
with an open circuit of the p-n junction and connection
of the positive pole of the current source to the chmic
contact. Curve 2 waa obtained by connection of a back bias
of 100 v to the p-n junction. Both ,,urves are -in full
agreement, For comparison, curves are introduced; whish
were obtained with ordinary Si-electrodes with a specific
resistance of 3 ohm.cm and 10 ohm.cm. The change i ii e I ec -
trode thickness in the case of the same specific resistance
exerts no influence on the anodic disoolution of S!, which
is in contradiction to the results obtained with germanium
(Ref 3). Thus it has been proven that the holes necessary
for the anodic dissolution of Si are essentially formed
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f- I.,_ 13
On the Particular Features of the Electrochemical SOV120-130-2-31,169
Dissolution of n-Type Silicon
between semiconductor and electrolyte, but not within
the semiconductor, A further confirmation of this opinion
was provided by the experimente made with reduced
(C 02-) and oxidizing (K Fe )-additions to the elea-
2 4 3 (CN)6
trolyte (Refe 6,7). There are I figure and 7 references,
3 of which are Soviet.,
PRESIENTEDs September 81 1959, by A. Ii, Frumkin, Academician
SUBMITTEDs September 81 1959
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S10201601134100610231031
B000054
AUTHORS, Yefimni-le. A. and Yerusalimchik, I. G.
TITLE: celState of Anodically Polarized
Investigation of the Surfs
Germanium in Alkaline Solutions
PERIODICALt Doklady Akademii nauk SSSR, 1960, Vol. 134, No. 6,
pp. 1367-1389
TEXT: The authors studied the state of anodically polarized germanium
by recording the curve of charge. To exclude semiconductor effects, they
used degenerateopolycrystalline germanium. The experiments were made in
0.1 N KOH at 20 C. The germanium electrode was anodically polarized at
various current densities for a certain- eriod. Then, the curve of charge
was recorded at a current density of 10 3 a/cm2 by means of an ;H0-1
(ENO-1) oscilloscope. Fig.1 shows the curves of charge after anodic polari.-
zation at the potentials -0-350 v and -0-330 v, and a duration of 10, 20,
60, and 120 sec. In all cases, the authors observedv at about-0-75 v,
a retardation of the potential increase which is due to the oxygen dis.-
charge on the germanium surface. In anodic polarization T = -0.35 v,
the amount of electricity needed is about 4-5*1o-4 coulomb/cM2 , and does
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Investigation of the Surface State of S10201601134100610231031
Anodically Polarized Germanium in Alkaline B004/BO54
Solutions
not depend on the time of polarization. The potential of about 1-4 v cor-
responds to the potential of hydro en separation on a pure germanium sur-
face in 0.1 N KOH at I - 10-3 a/eX The amount of chemically adsorbed
oxygen depends on the potential of anodic polarization. It is completely
eliminated by cathodic polarization at q 4 -0-35 v. With an increase in
the potential to -0-330 v, a horizontal step appears in the curve of chari/
at YFv -0-75 v. The total amount of electricity needed to remove the oxygeft-
rises by one order of magnitude, and now depends on the duration of the
preceding anodic polarization (jo-3 coulomb/cm2 at T - 10 see,
7-10-3 coulomb/OM2 at T - 120 see). The observed step makes the authors
conclude that with anode potentials higher than -0.35 v, part of the elec--
trochemically adsorbed oxygen is bound more closely to the surface. A
monomolecular GeO layer is formed. Fig. 2 shows that the retardation at
Y = -0-75 v can only be observed at anodic potentials below q - -0.180 v.
At higher potentials or after longer polarization, the horizontal step
disappears. Fig. 3 shows the curve of charge at anodic polarization with
I - 2.5- 10-2 a/cm2 (T - -0-03 v). After longer duration of polarization,
the potential of the electrode rises to +0.6 v due to slow diffusion
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Investigation of the Surface State of 31020 601134100610231031
Anodically Polarized Germanium in Alkaline B004/4054
Solutions
of OH- ions to the electrode surface, and a new retardation appears on
the curve of charge at If = -0.25 v. The experimental data show that the
total amount of 0 adsorbed to Ge may attain more than 10 monomolecular
layers, In the cane of anodic dissolution, an oxide layer forms which is
cathodically reduced at -0-75 There are 3 figures and 3-non-Soviet
referenceg.
PRESENTED: June 8, 1960, by A. 11. Frumkin, Academician
SUBMITTED: June 8, 1960
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B/076/61/035/003/006/023
Ll too C) 104S, 11'15,IZ73 B121/B203
AUTHORS: Yefimov, Ye. A. and Yerusalimchik, I. G.
TITLE: Anodic dissolution of germanium in the presence of reducing
agents
PERIODICAL: Zhurnal fizicheskoy khimii, V. 35, no. 3, 1961, 543-547
TEXT: The authors studied the mechanism of anodic dissolution ?S thin
germanium electrodes on addition of reducing agents such as C20 4 or I-. The
electrode used was a germanium lamina with a resistivity of 20SIem and a
diffusion length of I mm. The germanium lamina was 200 p thick. On one
side of the germanium lamina, a p-n electron transition was produced by al-
loying with indium. The potential of this germanium electrode with respect
to a saturated calomel electrode was determined for vario-Ls current densi-
ties at 200C, All polarization curves obtained in the presence of reducing
agents showed a distinct limiting current with potentials more positive than
0-5 v. The authors discussed the mechanism of accelerated germanium disaolu-
tion on addition of a reducing agent. Experimental data showed an additior&
supply of holes from the lower semiconductor layers to its surface in the
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S/076/61/035/003/006/023
Anodic dissolution B121/B203
presence of reducing agents. Electrons are injected in germanium during
the oxidation of reducing agents. This produces an electric field permit-
ting the supply of holes from the interior of the semiconductor to the sur-
face. This accelerates anodic dissolution. The increase in the saturation
current is higher on addition of I- ions than of C 02- ions to the solution.
2 4
This circumstance is due to partial reversibility of the reduction of
molecular iodine according to Gerisher and Beck's mechanism (Ref- 3: J-
Phys. Chem. (K. F.), 13P 389, 1957). There are 3 figures and 4 references:
2 Soviet-bloc and 2 non-Soviet-bloc. The two references to English-language
publications read as follows: Gerisher, Beek, J. Phys. Chem. (N. F.), 13,
389, 1957; Shockley, Bell, System Tech. J., 28, 435, 1949-
SUBMITTED: June 19, 1959
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-AUTHORS:
TITLE:
PERIODICAL:
JOL(3 116Y 111T1
89574
S/076/61/035/002/0111/015
B107/B220
Yefimov, Ye. A. and Yerusalimchik, 1. G. (Moscow)
-------------
Anodic dissolution of silicon in hydrofluoric acid
Zhurnal fizicheskoy khimii, v- 35, no. 2, 1961, 384-388
TEXT: The procens of anodic dissolution of p-type and n-type silicon with
specific resistance of about 1OD-cm in 2.5 N hydrofluoric acid at 200C has
been studied. The investigation is of practical interest for the electro-
chemical etching of silicon. The silicon samples tested were toward (111);
the minority carriers have'an ave~rage lifetime of 30-40 gaec. Polarization
and differential capacity were measured referred to a saturated calomel
ele:trode; the potential-veraus-time curves were measured with anNO-l
(M-1) oscilloscope. The method has been described by the authors in a pre-
vious paper on the dissolution of germanium (Zh. fiz. khimii, ~J, 441, 1959)-
Fig. 1 B ows the rtential for anodic dissolution at current densities bet-
ween 10-9 and 10- A/cm2. n-type silicon shows a clearly marked limiting
current which is still increased by adding potassium ferricyanide to the
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89574
Anodic dissolution of ...
S/076/61/035/002/011/015
B107/B220
solution. For p-type silicon, however, T is a linear function of log I
between 10-~-6 and 5-10- 3. It follows therefrom that the dissolving process
is determined by the number of holes at the silicon-electrolyte interface.
The dissolution causes the formation of an oxide layer which is dark on
p-type silicon and dissolves hardly in concentrated hydrofluoric acid, but
with vigorous evolution of hydrogen in cold potassium hydroxide. The ox-
ide lay'er on n-type silicon is much thinner and reacts hardly with potassium
hydroxide, but is dissolved in concentrated hydrofluoric acid. Apparently,
the oxide layer on p-type silicon consists mainly of bivalent, and that on
n-type silicon of tetravalent silicon compoundu. Differential capacity was
measured at 200, 1000, and MOM cps. (Figs. 2 and 3)1 the curves corre-
spond to those for germanium, but the capacity is lower. For p-type silicon
it is about one order of magnitude higher than for n-type silicon; this is
due to the fwt that:h the 1-Ater t~_- impov6rishad carrier band is broader. The chwige
of the electrode potential after reversing from cathode to anode direction
is shown in Fig. 4. Conclusions: The first stage of anodic dissolution is
the electrochemical oxidation of the electrode surface) then, the hydro-
fluosilicic compounds formed on the surface enter the solution; this process
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3/07 61/035 002 011 0
kiodic dissolution of B107Y5220
~.s, however, limited by the number of.holes at the semiconductor-electrolyte
.interface. If there is an insufficient number of holes (as in the case of
io
~A-type silicon)y the dissolution of the silicon oxide compounds formed on the
durface is rendered difficult and electrochemical oxidation of the electrode
Aurface continues unimpeded. Probably, this is the reason why tetravalent
.and bivalent silicon compounds are formed on n-type and p-type silicon,
respectively. There are 4 figures and 5 references: I Soviet-bloc and
.4 non-Soviet-bloc. The references to the three Engliah-language publications.
read as follows: Uhlir, Bell System Techn. J.j J~j 333! 19561 Turner,
J. Electrochem. Soo - P j_O.~p 402 f 1958 Flynn, J. Electrochem. Soc. j-0-2) 715)
1956-
SUBMITT ED -June 10, 1959
..Legend to Fig. 1: Anode polarization in the dissol 'ution of silicon:
'(1) n-type silicon in 2-5 N HF;(2) p-type silicon in 2-5 N HF;(3) n-tYPe
silicon in 2-5 N HF + 0 -05 N K Fe '(CN)6-
Legend to Fig. 2: Differentiai capacity for p-type silicon: (1) 200 cps;
(2) 1000 cps; (3) 10000 cps.
Legend to'Fig. 3: Differential capacity for n-type silicon: (1) 200 cps$-'
dard 3/5 (2) 1000jI(3)~ 10A00 CPs.
Na
FOE
ME I M WOMOMMOR"
-M-MORIM

3/076/61/035/002/011/015
Anodic...dissolution of B107/B220

__.__'.~89574
S/076161/035/002/011/015
dissolution of B107/B220
"~'j,O bege
Le
to Fig. 4: Electrode potential6 for th6
dI of current directii
!-~rever on: (1) P-type
i~ Si:Lj
io-4 A/cm2; (2) p-type silicon
con,
4
1 2.16- A/cm (3) p-type siliconj
-4 2
5.10 -type silicon,
I A/am (4) n
-A
jT
. . .....

S/076/62/036/001/008'017
-B 10 7 /13110
AUTHORS, Yefimov, Ye. A., and Yeruealimchik, 1. G. (Moscow)
TITLE: Study of the surface condition of anodically polarized
germanium in acid solutions
PERIODICAL: Zhurnal fizicheskoy khimii, v. 36, no. 1, 1962, 98 - 102
TEK'V-. The surface condition of a germanium anode has been studied at a
current density of 10-5 to 10- 1a/cm 2 in 0.1 N H2so4 at 200C. All the
experiments were made with polycrystalline, non-semiconductive, degenerate
germanium with an impurity concentration of nearly 0.01%. Preliminary
tests have shown that germanium of this type behaves in anodic dissolution
like p-type germanium. The charge curves were measured with an 9H0-1
(ENO-1) oscilloscope. The germanium electrode was anodically polarized
at different current densities for some time, whereupon thel -Q curve was
recorded at a cathode current density of 10-3 a/cm 2. The germanium
electrode was etched in CP-4 (SR-4) before each experiment. In addition,
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S/076/62/036/001/oCr,,/017
Study of the surface condition ... B107/B11O
its resistance and capacitance were determined between 60 and 5000 coo.
It has been found that an electrochemically adsorbed layer of oxygen is
formed on the germanium surface at a potential less than 0.38 v. The
layer has a thickness of about 2 - 13 oxygen atoms, which is independent
of the DOtential and of the time of polarization. A monomolecular layer of
a defined compound of one germanium atom per oxygen atom starts forminE
above 0.33 v. This monomolecular layer exhibits a high resistance and
can be entirely dissolved cathodically. At 0.57 v and more, thick,
macroscopically detectable layers of GeO, the thickness of which grows
with the potential and with the duration of polarization, are formed on
the germanium surface. The oxide is not completely dissolved by cathodic
polarization. The potential required for the separation of oxylgen on it
is higher than on pure germanium. There are 5 figures and 5 references:
1 Soviet and 4 non-Soviet. The two references to English-language
publications read as follows: D. Turner, J. Electrochem. Soc., 103, 252,
1956; J. Law, P. Meigs, Semiconductor Surface Physics, N. Y., 1957, P. 383.
SUBMITTED: April 6, 1960
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5/076/62/036/004/005/012
BIOI/B110
AUTHORS: Yefimov, Ye. A-j yerusalimchikt I. G-p and Sokolova,
twoscowT
TITLE: oxidation of germanium surface during chemical etching
PERIODICAL: Zhurnal fizicheskoy khimii, v- 36, no- 4, 1962, 765-769
TEXT: A report is given on experiments for the purpose of studying, by
means of charging curves, the oxidation of the surface of polycrystalline
Ce, which was treated with various etching agents. The Ge contained a
maximum of 0.011,16 impurities. The following substances were used'aa etching
agents: (1) CP-4, consisting of 50 cm3 Hijo 3, 30 cm3 cH 3COOHP 30 cm3 HFf
and 0.6 cm3 Br2; (2) etching agent no- 5 of S- G. Ellis (J. Appl. Phys.f
29, 1262, 1957); (3) etching agent no. 8 of Ellial (4) 20 cm3 H 202P
1 mg KOH; (5) 20 cm3 HF, 10 CM3 HNO 23 11 80 v 5Q cm 3 H 0, 1 5 g K Cr-0-
3' 5 OE 2 4 2 2 Z-r
and I g N9Cl. The charging,curves were plotted at 200C in 041 N 11280 4 and.
cathodic current density of 10-3 a/cm2 (Fig. 1). The stationary potentials
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5/076j62/036/004/005/012
oxidation of germanium surface B101/B110
of the Ge electrode after etching for 15 sec were measuredy and also the
2) required for removal of the oxygen
quantity of electricity (coulomb/cm
bound to the Ge surface after etching the sample for 5, 10, 15, 30 or
60 see. Results: (a) on the germanium surface, each of the etching agents
formed oxide films of a structure and composition specific to the etching
agent; (b) the most homogeneous film is formed by the H 0 etching agent
2 2
no. 4; the charging curve of Ge treated with this etching agent shows a
clearly horizontal course for -0-3 vi (c) with the exception of the
etching agent no. 4, the specific effect of all etching agents is loot
after 1-4 hrs exposure to air. The quantity of electricity necessary for
reducing-the oxide film was 4-3-10-3 after I hr exposure to air; 5-0-1o-3
after 2 hre; and 5-6-10-3 coulomb/cm2 after 4 hrap from which the formation'
of Ge021 which is reduced at T -" -0.2 Y, may be inferredp this being in
good agreement with R. J. Archer (J. Electrochem. soo.t 104t 619t 1957)-
There are 4 figures and I table.
SUBMITTED: : June(30, 1960
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S/076/62/036/004/005/012
Oxidation of germanium surface ... BlOl/B110
Fig. 1: Charging curves of Ge after 15 see etching. (I)9 (2)l (3), (4)
and (5) etching agents seen in the body of the 2abstract.
Legend: ordinate v,- abscissa coulomb/CM
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3 7631
S/076/62/036/005/006/013
BJOI/B110
79 0
AUTHORS: Yefimov, Ye. A., Yerusalimchik, 1. G., and Sokolova, G. P.
TITLE: Blectrochemical evolution of hydrogen on monocrystalline
silicon in hydrofluoric acid solution
PEIRIODICAL: Zhurnal fizicheskoy khimii, v. 36, no. 5, 1962, 1005 - 1009
TEXT: The authors studied the electrochemical reactions of P-and n-type
Si in 2.5 11 H? and measured (a) the H 2 overvoltage at 2-5*10-6 _ 5-10-2
a/cm2 with preceding I-hr cathodic polarization at 1. . 10-2 a/am2; (b)
the oscillograms for current inserzion with Si as cathode; (c) the anodic
charging curve at I a ' 5-10-5 a/cm 2 with precedingcathodic polarization
at various potentials. Results; (1) Slowly taken cathodic polarization
curves i-L- f(log 1) are equal'for n- and P7type at V -0.7 v and obey
Tafel's equation, b,-,;0.17 V. With more negative q the potential rises
quickly: for p-type Si at 10- 3 a/cm2 for n-type Si at 10-2 a/cm 2.
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Electrochemical evolution of... B100110
(2) Oscilloscopic measurement of the potential by an )P-1 (EI'10-1)
oscilloscope, synchronously connected with a sawtooth pulse generator,
showed no change of the polarization curve for n-type Si, and an increase
of the potential by 0.35 v for p-type Si. (3) The oscillograms for
-4 2
current insertion are equal for both types at 1 0- 10 a/cm . At
Ic- 10-3 a/cm 2, the curve for p-type Si shows a distinct peak 2 v high.
(4) The anodic charging curves for Si polarized at -0-5 v show a retarda-
tion of the potential at I,> -5 a/cM20 This suggests'the formation of
,~, 5 - 10
a surface compound from Si and H at -0.5 v. Two processes are possible
for H evolution: (A) Si + e- + H+ SiH + e + H+--Isi + H 1. The
2 val 2
second reaction is much retarded. for p-type Si. (B) Hydrogen forms dipoles
with outward-directed negative poles on the Si surface. With n-type Si,
the negative charge of the surface is compensated by the positive charge
of the surface barrier, and fur~.her hydrogen adsorption is restricted.
I.ith p-type Si, the positive pole of the dipole is a hole. As p-type
dipoles do not reach into the body of the semiconductor the formation of
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B/076/62/036/005/006/013
Electrochemical evolution of ... B101/B110
further dipoles and further hydrogen adsorption is possible. There are
4 figures.
SUBMITTED: July 27, 1960
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F&IN IMMA

UYUMOV, Ye.A.; YERUSALIMCHIN, T.G.; SOYOf,fitrAt G.F. (Mo3oow)
State of the surface of anodically polarized silicon In hydrc-
I
fluoric acid solutions. Zhur. fiz. khim. 36 no.6:1219-12.21
Je ~ 62) (MIRA 17~7)

W44
S/076/62/03'/006/005/011
BIOI/~144
AUTHORS: Yefimov, Ye. A., and Yerusalimchik, 1. 0.
TITLE: Effect of the-bichromate ion on the anodic dissolution of
germanium
PEIZTODICAL: Zhurnal fizicheskoy khimii, v. 36, no. 8, 1962, 1791 - 1794
TE.',2: Proceeding from observations rrade by F. Beck, H. Gerischer (Z.
"lectrochem., 63, 943, 1959), the behavior.,of p- and n-type Ge
(resistivity 1.0 ohm-cra, diffusio-f. length 0.5 mm) in 0.1 N H2 so4was
studied in the presence of 0.15 - 0.03 1", V.2 Cr207at ro-om temperature.
Results: (1) ."lith p-type Got the potential of anodic dissolution increased
in the presence of the bichromate by-0.2 v for the whole range
investigated (0 - 1.6 ma/cm2). (2) "With n-type Go, the potential of
anodic dissolution increased whereas the saturation current d;opped to
nearly one-half. Exposure of the Ge electrode to light eliminated the
bichrom9te effect. (3) On thin Ge electrodes with p-n junctiona. small
bichromate effect with reverse bias and a reduction of the saturation
Card 1/2

S/076/62/036/008/005/011
Effect of the bichromate ion ... B101/B144
current with open p-n circuit vere observed. Conclusion: The Cr 2 02- anion
7
is adsorbed on the positively charged Ge surface. Since he valence
electrons of the ion are drawn to the oxygen atoms, the Crg+ ce.iter
attracts electrons and repels holes. This inhibits the anodic dissolution
and reduces the saturation current. On exposure to light, this effect is
compensated by the intense generation of holes on the surface. There are
3 Z~'~
igures.
SUBYITTED: December 8, 1961
Card 2/2
RMT
LOMIMMININ
FM MM I MINI R, pmr. ~==

ION SOV/6448-.
PHASE I,BOOK E(PLOITAT
Yefimov, Yevgeniy'Ale 1coandrovich, and 'Josif GrIgor 'YeVich Yerusalimchik
E,Iektrokhimiya germaniya i kremniya (Blecirochemistpy,of Germanium
and Silic6n) Mos-cow, Goskhimizdat, 1963. 180'p,. -Errata slip
insdrted.,. 5000-coPies printed.
Ed.,.! 'A. T. Kochnev; Tech. Fd.:, V. V.'K6gan.,
-the book is Intended for seientific.'%workers, engineers,
-and technicians working in the semiconductor indubtry., It may
also be.useful to advanced students s~ecializinig both in semi--
conductor engineering and in electrochemistry.,.
~COVEROE: The book is a.generalizatiop of investigations carried'out',
by.Soviet afid non-Soviet scientists in-a new area of physical
chemistry, the electrochemistry of semiconductors'Buch as germanium'
and qilicon. It offers a systematic outline of the structure of
theelectrib d6uble layei~ at the semiconductor-electrolyte inter-
face,and the kineftes of the anodic disaolutio'n of germanium and
'Card 1/17-

El eet'r~ o'e'hemlst ry of Germanium and Si I i oo7n' SOV/6448
-18ilicon and'provides date on.other electrochami6al-reactions
.'oecuring on'germanium and silicon electrodes. AJpecial chapter
has been devoted to a discussion of-electrochemibal operations
perform6d'imthe production of semiconductor devices'.. Thd authors
-thank Ye, N, Faleglos., Can"didate of Ch6mical, Scie~ceso for 'his
,valuable comments.' Each-chapter is Accompanied'by-references.
TABLE OF CONTENTS:
.Forew6rd
I.~. Structure of the Sealponductor-,Ele6trolyte.
Interfa
ce 7
.1. Surface properties of a semicondilctor
7
Chargea layers at seniiconduotor'-electrolyte.
boundary-
Bibliography 22
Card

I
~_,Xp*A*; SAPKO, V.N.; GREBENYUK, V.P.; PIORO, E.Ch.; SHCHaTNYY,
P.M.; KSENZUK, F.A.; SHIRINSKIY, D.I.,* TOISTYKII, V.I.
Rapid top pouring of rimmed steel into ribbed ingot molds. Metal-
lurg 8 no.lltl7-19 N 163v (MIRA 16:12)

ACCESSION NR: AP4033398 S/W(6/64/038/003/0589/0592
A. (Moccow); Yeruaalimchik, X. G. (14oscow)
AVDIOR: Yefimoy~
reneltioa on tho anodic
Effects of electric and atructurel haterog
~diasolution of germanium.
SOURCE: Zhurnal fizicheLoy khimii, Y- 38, no. 3,, 1964) 589-592
TOPIC TAGS. Germanium, anodic dissolution, polarization., anodic polarizet-ion,
whole, electric heterogeneity, structural. heterogeneity
!ABSTRACT: The purpose of this investiGation was 'to find the cause of the discre-
pancicG--between the theoretically calculato-d limiting current for the anodic
dissolutioi~ of gemanium and the much greater experimentally observed current.
Since the ordinary single crystals of germaniwa are not strictly homogenious
specially grown crystals of n-germanium withJ0 = 3 ohm,cm and length of the order
of 0-7 mm, containing ~ minimum amount of impurities and the density of disloca-
tions.of 50 dioloc./cm and also germanium with the a
e electric rd physical
loc./cm were used for
parameters but having a density of dislocations -6910 dis
this investigation. The anodic polarization curves were obtained by the potentio-
.:Card, 1/4

IACCESSIMI NH: AP4033398
static method in 0.1 N 112S04 (Fig- 1). The experimental results show that the
.increase of the limiting current during the anodic dissolution of germanium is
tassociated with an additional Generation of boles on some parts of the electrode
surface. A higher concentration of Cu and Ni on such parts of the electrode may
lead to the formation of the high resistance micro regions where the acceptor
'impurities compensate for the main part of donor impurities or it may lead to
segreGatioa of Cu and Ni into a separation phase, primarily at the places of dia-
ruption of the, crystal lattice. In the areas or germanium on wbich the conductivi-I
:1ty is close to the bulk conductivity, the limiting current due to holes is much
$Greater than on bulk n-germanium. U-
pon increase of anodic polarization these
zones may completely change the type of conductivity. The p-regions which occur
at the n-germanium electrolyte interface will carry a large fraction of currentj
thus individual areas of the electrode surface dissolve more rapidly than others.
!A segregation of Cu and Ni in a separate phase in the germanium Prystal, may be
:Produced due to break-through and local generation. This was verified by measuring:
~the photoelectric potential as a function of the potential of germanium electrode I
"The authors express their gratitude to L, It Koleanik and Yu. A.
i in 0-1 11 H2S04-
:Kontsevoy for their help and valuable suggestions during discuoaioa of the reflultat"
Orig. art. has: 2 fitpires.
2/4

4
mmmigm
EUCL: 01

ACCESSION NR: AP4033398 B14CLOSURE s 01
Fig. lo Anodic polarization curves obtained
by the potentiostatic method in 0 - 1 H ",':P04 SOW
vith n-germanium electrode.s. Resistiviiy of, j
germanium was 3 ohmoem. U
I Z 0-7 mm, 50 dtaloc./CM2
2 L = 0.7 mm, 6*40 disloc./CM2
3 L = 0.03mm, 101 disloc./c~a2
L = 0.0_~=, (upecimen 2 after removal
of Gu Ni impurities
-.1
Card 4/4

ACCESSION MR: AP4033404 S/0076/64/038/003/0720/072 3
AUTHORS;-Yefimov. Ye.A.; Yerusalimchik, I.GS; Gorgoraki, Ye.l.
TITLE: Reduction of persultate ion at a germanium cathode
SOURCE: Zhurnal fizicheskoy khtmil, V. 38, no. 3, 1964, 720-723
TOPIC TAGS: persulfate ion reduction, reduction, germanium cathode,
n type germaniumt p type germanium
f
t ABSTRAOT: Because of the contradictory data given In literature
i
on the reduction of persulfate Ion at germanium electrode,, this
reaction was studied by the potentiostatio pol4rization method and
also via measurement of the photoelectric potential of the germanium.
electrode, This permitted determination of the magnitude of the
curvature of the energy zone on the electrode'surface. 2lectrodes'
from n- and p-type germanium with specific resistance of 1.5 ohm.
)(cm and diffusion zone length of 0.7 mm were used. A series of
experiments were made on a degenerated polycrystalline germanium
ILwhioh does.not have semiconductor properties and also using electrod-
e 'with p-n transition. Polarization curves taken in 0.001 N "2S206-

till
Vo
Ir
AcassioN NR: A2403304
on'n- and p-degenerated germanium show that under'given oonditio a
the reduction process'does not depend on the type of ele9trods.
.conductivity and that*a limiting current of ivO.35 ma/cm7-d I a the.
normal spdoifio current for persulfate Lon diffusion to the
electrode surface. The addition of an Indifferent eleotrolyte to a'.
0.001 N K S OA solution decreases somewhat the Inhibition pf the
electroch9mioll reaction. It wis found that on increasing the
coi2oontration of the persuifate ion In the adlution, the polarizatioz
curve s f or p- and n-garmanium. begin to dif far and at 4v = -0. P,, -j* -0, 2,v
the rate of reaction increases. With increase of the concentration..
onium persulfata the ph9topotential Increases and the value of,
of amm
the potential of flat zone isjdisplaced toward the more positive
potentials for the p- and n-tjbe germanium electrodes. Since the
polarization curves on n-~ andp-garmanium corresponds to poto t als.1
n, I
-0.2 -w -O.lv, It was concludeA that in both cases the reaction is
Inhibited. On the basis of the lack of limiting c = out for the
diftusion of electrons in the,p-gormanium it was assumed that also-
trons of the valence zone'take part In the reduction or the rato of
ryfaoe reoombiTln at the ~lectrolyto boundary la very great.
Bu
9 ran*
arto hael 9u
It

-- - - , - - - ,
I
I
T i
I
11 1
I I
1. -
;I !AOOESSION NR: AP40334b4'----- I'
11
1.
I.:
.

YEFIMDVS, Ye.A.~ YERUSALIMCHIK, LG.; SOKOIDVA, G.P. (~oskva)
Electrochemical behavior of the silicon electrode in solutions
of owidation agents. Zhur, fiz. khim. 38 no.9:2172-2175 S 164.
(MIRA 17.12)
M=ntm 4AMA,-WEA

L 62f 04--65 44 7(m )/Eh"! ( t j ( b !JP(c JD
ACCESSION 11P_ APS0184S4 UR/0364/65/001/001/0818/M21
541.13:621.315.592
AUTHOR: Yefimov, Ye. A.-I Yerusalimchik, 1. G. i
ITITLE: Anodic dissolution Df_&2L1i= arsenide
SOMWE. Elektrokhimiya, v. 1. no.
7gS65, 81
7OPIC TAGS: galli= arsenide, slectrochemistry, anodic dissolution, photoelectric
semiconductor. oxidation
ABSTRACT: T'he anodic dissolution of gallium arsenide proceeds with the participa-
tion of holes. For this semiconductor with a wide forbidden zone the ma-in potential!
jLunp takes place in the space charge region. This investigation was carried aut by
means of anodic polarization curves, measurements of photoelectric potential, Jif-
femntial capacitance, cathodic charging curves and current efficienc-f. Single
crystals of n-type galliLm tirsenide (doped with telluri=) were used as electrodes.
The electron concentrations in these crystals were 1018 and 8'1016 cm-3. Scne elec-
trodes wem made from p-Me gallium arsenide (doped with zinc) in which the concen-
i0n '~'f 110166 was [~.1010 nd 1.114 ma-3. oriented along the III plane. The poten-
tio,itatic curves (Fig. i of the indicate that tho d1santution of n-typv
Card 1/4

L 62804-65
ACCESSION RR: APSOLS454 -6 a/cM2,
.gallium arsenide Is retarded at current dcnsity of 10 . At 1.2-1.3 V a
breakthrough at the electrolyte boundary takes place, and the avalanche of cm-nent
carriers is produced. In 1 N 112SO4 the potential of gallium arsenide is indepandent
of the concentration of gal-litri ions in solution, apd for n-type it is 0.3 V mire
inegative than for p-type. Analogous curves are obtained in 0.1 M H SO In
4*
0.1 N KOH and 1 N KOH the curves for p-type gallium drsen1de are shifted 0.70-0.75
.mo.--,- positiv,~ as compared with acid solutions. in these solutions the potential of
,n-tyr?e is more positive than of the p-type. Illumination of the electr--de surface
;causes a large shift of the potential of n-type gallium arsenide in the negative di-
rection and essentially results in elimination of the retardation of the anodic re-
act'"on Jue to hole deficiency. Illumination of p-type gallium arsenide resu3l:s in
potQntial shift in the posLtivE direction- Analyses of anodic dissolution pr