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International Journal of Trend in Scientific Research and Development (IJTSRD)
Special Issue on Innovative Development of Modern Research
Available Online: www.ijtsrd.com e-ISSN: 2456 – 6470

Technological Features of Manufacturing APV Films

2
1
1
2
Turaev B. E , Rakhimov N. R , Ulugov B. D , NamozovJ. Sh
1 Ufa State Petroleum Technical University, Uzbekistan
2 Termez branch of Tashkent State Technical University named after Islam Karimov, Termez, Uzbekistan

ABSTRACT on the absorption coefficient, the wavelength of the incident
In this work, we describe a technique for obtaining APV light, film thickness, the diffusion length of carriers, rates of
films from binary semiconductor compounds CdSe, CdTe, surface recombination at illuminated and unlit faces, surface
CdTe: Cd by thermal evaporation in a vacuum. recombination of carriers, and the depth of light penetration.

Coefficients that depend on the photosensitivity of the a1 and

KEYWORDS: Films of anomalous high photovoltage (APV), a2 transitions are included in the expressions for the
semiconducting compound CdSe, СdTe, CdTe: Cd, binary transition photocurrents, i.e.jF1=а1IorjF2 =а2I; jF1–p-n-junction
semiconducting compound photocurrent,

INTRODUCTION jF2 - photocurrent of n-p-junction,
Knowledge of the characteristic microparameters of APV I - illumination.
films allows us to clarify ideas about the nature of the
generation of photovoltage in micro-photocells, and by them, In this case, the most important tasks are the development of
in particular, the APV film is evaluated as a device and its scientific methods for obtaining APN films (from various
scope is determined. Usually, when determining the materials) with specified properties and methods of effective
characteristic microparameters to find the mobility, they control over their properties under various conditions.
resort to the photo hall effect, the interpretation of the
A wide class of semiconductor substances, in the films of
results of which in film samples is associated with great which the APV effect was detected, confirms the possibility of
difficulties. It was shown in [1-2] that, without referring to obtaining APV films from any semiconductor [3-4].
photo-Hall measurements, using the spectral dependences of
APVN and APV effects, it is possible to determine To obtain APV films from СdTe and Sb2Se3 compounds, we
characteristic microparameters, such as carrier mobility, used the method of thermal evaporation in a vacuum. The
diffusion length, number of micro-photoelements, and vacuum unit is assembled based on a mechanical fore-line
surface recombination rate. pump of the RVN-4 type and a steam-oil diffusion pump of
the N-01 type, which provides a pressure of about 10-4 mm
APV-films (abnormal photovoltage) [2-3] are a functional
Hg. Art. Crucibles made of aluminum oxide or beryllium were
converter that transforms the luminous flux of intensity F0 used as evaporators [5-6].
into anomalously high photovoltage VAPV. According to the
adopted model [4], this transformation consists of three The evaporation temperature of the semiconductor was
stages. achieved by controlling the current. The substrates were
heated using an oven, the design of which makes it possible
First, the creation of a photocurrent IF, due to photo
to change the substrate temperature up to 600 ° C. The
generation and spatial separation of nonequilibrium carriers
temperature on the substrate and the evaporator was
at each micro p-n junction. Secondly, the emergence of
controlled by chrome-alumni thermocouples attached
elementary stresses at micro p-n-junctions as a result of the directly to them. Glass and quartz with metal contacts were
accumulation of space charges created by the photocurrent.
used as substrates.
Third, the formation of an anomalously high photovoltage by
summing the elementary photovoltage at p-n junctions. The technological mode of obtaining APV films and the
choice of a material depend on a large number of factors and
Materials and Methods
parameters, such as the temperature of the evaporator and
In this article, we propose methods for creating optically
the substrate, the deposition angle, the film thickness, the
controlled microcircuits based on a thin-layer AFN film.
composition and pressure of residual gases in the vacuum
The physical mechanism responsible for the appearance of chamber, and the conditions for the heat treatment of the
the APV effect in semiconductor films with a periodic p-n- films after deposition. In this case, each semiconductor
pstructure is known to be associated with incomplete material corresponds to its optimal mode, and often small
compensation of photovoltage in p-n and n-p junctions due deviations from it, even in one of the parameters, lead to the
to a special technology of oblique deposition of films on a disappearance of the APV effect in the films being produced
substrate. This small uncompensated photovoltage in the p- [7-8]. Therefore, the development of a technology for
n-p cell (VH<KT / q) arises either due to asymmetric obtaining APV films from a particular material requires a
illumination or due to the asymmetry of the dark saturation large experimental research work, a large (number) number
currents of p-n and np junctions. Both of the above factors of test sprays with a sequential variation of several
can participate in the formation of the AFN effect. technological parameters, their combinations, and finding
parameters specific for obtaining the APV effect on films
The practical aspects of the effect are determined by the from a given(selected) semiconductor material.
efficiency of APN films, which are closely related to the
photosensitivity of transitions, the value of which depends

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