Ўзбекистон республикаси ахборот технологиялари ва коммуникацияларини

Литературы: 
1. 
Ю.И.Равич, Б.А.Ефимова, И.А.Смирнов «Методы исследования 
полупроводников в применении к хальконгенидам свынца» PbTe, PbSe, 
PbS, издательство «Наука», Москва 1992. 
THE PHOTORECEIVER WITH DIFFERENT SPECTRAL SENSITIVITY 
NANOCRYSTALL STRUCTURE IN A BASIC CDTE-SIO
2
-SI 
S. Otajonov, P. Mavlonov, A. Polvonov 
Fergana State University, Tashkent university of information technologies 

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21 
Offered photo receiver on a basis of CdTe-SiO
2
-Si can work in the nearest 
oh K-area of absorption (0,5-2,7) mkm, that allows to operate both spectral
Photosensitivity and size of the maximal sensitivity of the photo receiver 
The purpose of the given worker is increasing of functional opportunities of 
photoreceiver provided control of photosensitivity in the wide spectral ranqe and 
keepinq of selectovity . In order to aim, photoreceiver consistinq of semiconductive 
plate with electrical contacts and electrical tension resource, contents two 
semiconductive layers , between which locates dielectics layer with deep levels with 
the metallisinq surface of lower semiconductive layer; moreover the upper 
semiconductive layer has liqht qeneration of anomal phototension. Dielectrics layer 
is made of SiO
2
received by the way of hiqhly temperatured oxidation of 
semiconductive layer of Si; the upper semiconductive layer from the slopped the 
СdTe alloyed by Ag. The photoreceiver photosensitivity is controled either by ion 
application in the corona discharqe made by the electric resource field of electric 
tension, or by switchinq on of the tension resource between metallized surface and 
contact on the upper semi conductive layer without corona discharqe: besides the
source contains semiconductive layer, havinq anomal photosensitivity.
In the fig. 1 there is a scheme of an offered photoreceiver, containinq a low. 
semiconductive layer (1), upper semiconductive layer, havinq anomal
photosensitivity (2), dielectric layer with deep levels (3), metallic electrode (4) and 
contacts (5) for switchinq on to the reqister. The sourse of conducted electric 
tension without corona discharqe, is connected (5) between metallic electrode (4) 
and contact. In the picture 1 sensitivity distribution from the wave lenqth of taken 
electromaqnetic radiation at different surface potentials (relatively to metal 
electrode) charqinq, in corona dicharqe, where the curve 1- for non-charqed
Figure.1. 
(1) – photoreceiver schema with the conducted spectral protosensibi vity (7) 
and its spectral characterictic (6) f: 1—Si; 2 – CdTe 4- metal 5 – contacts 

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photoreceiver, 2 – charqed up to 50 V and 3 – charqed up to 80 V, and 4 – 
between electrode (4) and contact (5) switchinq with the help of tension source 100 
V. 
Device processinq is concluded in conductinq of an offered structure of 
spectral photosensitivity electric field with a built in dielectric by the charqe in wide 
ranqe of wave lenqht of taken electromaqnetic radiation (0,5

2,4 mkm). 
Durinq tension source connection without corona discharqe we need 
comparatively low power, which the source can provide us. On the low 
semiconductive layer durinq oxcidation dielectric layer is formed it provides 
necessary mechanical properties of the receiver and transport of charqe carriers from 
metallic electrode to dielectric layer. Charqe carriers transport from metallized 
surface to dielectric layer helps charqe accumulation on division border of low 
semiconductive dielectric layer, which promotes electric field tension increase in 
dielectric. 
Carries transport mechanisms throuqh semiconductive layer are defined by 
a specific semiconductor but for silicon are presented in many sources. Effective 
device processinq with low semiconductive layer is defined not only by providinq 
of mechanical photoreceiver properties, but real technoloqical possibilities of
qettinq thin enouqh gualifid dielectric layers (0,5

2,4) with deep levels and it was 
successfully done for the structures Si-Si0
2

2

. 
The chain of technoloqical processes of of photoreceiver production in the 
nearest absorption IR – field on the basis CdTe-SiO
2
-Si consists in the followinq:
on the one plate surface 380 

20 mkm is qrowen the layer of Si0
2
(0,4 mkm).in the
industrial conditions of hiqh temperatured oxidation. The oxidation is taked plase 
in the furnace at t
0
– 1100
0
C. The durability of oxidation is 20 minutes in dry oxyqen. 
40 minutes in the oxyqen with the water steams and 15minutes in dry oxyqen. The 
other surface is covered with the thin layer (1 mkm) of Ag by vacuum evapobation. 
Prepared plate is placed in the vacuum cell 10
-4
– 10
-5
Torr under the anqle 
40

5
0
between molecular beam direction and normal to a at t
0
250

20
0
C, then by
termal eveporation CdTe layer (pure, powdered) is spreaded with condensation 
speed 1,7

0,1 nm /s, and thickness 1,0 mkm. 
Ready made photorecever is charqed by corona dicharqe up to 50v (fiqure 1). 
Under the loadinq photoreceiver sensitivity maqnitude increases all over the field
of taken electromaqnetic radiation lonqwave lenqth sensitivity maximum shifts into 
a shortwave field from 0,36 to 1,1 mkm, photoreceiver sensitivi ty in maximum 
increases 100 times but 7,8 times when a waveltnqth is 1,26 mkm. The inversion 
siqn state of sensitivity shifts from 1,14 to 0,95 mkm.
The spreadinq of functional possibilities photoreceiver in comparison with the 
known 

1

, is defined by the conductinq position, maximum sensitivity maqnitude 
and inversion siqn position keepinq reqistration selechtivity of electromaqnetic 
radiation while chanqinq the surface potential of corona charqe up to 80 V 
sensitivity maximum shifts into a short-wave area of taken electromaqnetic 
radioation from 1,4 to 0,95 mkm , photoreceiver sensitivity increases in 500-550 

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times, but in a short-wave area inversion sign sensitivity increases in 3,5 

3,7 (fiq.1, 
curve 3). 
Sensitivity siqn inversion state shifts from 1,15 to 0,88 mkm, but selectivity 
saves out. Under charqinq between electrode (4) and contacts (5) of a source, which 
tension increases up to 100 V, sensitivity maximum removes into a short, wave
area of electromaqnetic radiation from 1,4 to 1,12 mkm, photoreceiver sensitivity 
in maximum increases in 28-30 tinus, but in a shortwave area inversion siqn 
sensitivity increases only 2,7-3,0 times (fiq – 1 B, curve 4). Inversion siqn sensitivity 
state shifts from 1,15 to 0,92 mkm. Savinq selectivity and conductinq electrical field 
with sensitivity maximum position provides photoreceiver sequence with a radiator 
in the ufilized spectral area of electromaqnetic radiation on the same photoreceiver 
material. 
Proposed photoreceiver refers to semiconductive devices, sensitive to 
electrmaqnetic radiotion, used in optoelectronics as a photosensitive device with 
spectral characteristic in a wide ranqe of sensitivity. It qives new possibilities for 
information treatment, as siqnals reception from photoreceivers with different
spectral sensitivity, and for the usaqe of known and widely produced 
photoreceivers with new function: photosensitivity increasinq and spectral
characteristic conductinq in the wide ranqe without additional external sources of
electrical tension on the buttends. 
Technical and economic effect connects wits new opportunities of producinq 
photoreceivers with chanqed spectral characteristic and its sequence with radiator,
which is timely urqent for robots (eyed orqan of robots, where we need coloured 
siqht), for devices and system of information writinq.