PbS photoconductive detectors

URALSEMICONDUCTOR, RESEARCH CENTRE

 Highly-reliable PbS photoconductive detectors of (0,3 — 3,3) µm range.

LEAD SULFIDE INFRARED DETECTORS (0,2 – 3,6) microns

Photo-electric parameters
for sensitive area А=1,30х1,30 мм²
Type of detector:
PbS Photoconductive Detector
Т=295К
Т=235К
Spectral range of response, microns
0,2-3,3
0,2-3,6
 Maximum¹ of spectral response, microns
2,35-2,55
2,55-2,75
Detectivity,
D*λmax; 2400), sm W -1Hz0,5
(2,0-3,4))x1010
Detectivity,
D*λmax; 500), sm W -1Hz0,5
(1,5-2,5)x1011
Photo Sensitivity, V / W,
no less than
(7-13)x104
(7-20)x105
Time constant, μs (10-6s)
45-75
250-350
Dark Resistance, kOhm /
40-120
130-500
Maximum permissible level of  incident energy, W/sm2
5х10-2
10-2
Supply voltage on a circuit
(RD+REq), optimal, V
24
24
Operating range of temperatures, °С
(-60) — (+60)
(-60) — (+60)
The offered sizes of sensitive element, mm

1,0х1,0; 1,3х1,3; 2х2; 1х5; 3х3; 4х4; 5х5; 10х10

1,0х1,0; 1,3х1,3; 2х2; 1х5; 3х3; 4х4;5?5

Entrance window (cases see in appendices)
Glass; silicon;
UV-quartz; IR-quartz
Silicon;
IR-quartz

1) The data for a standard film thickness 0,38-0,43 microns. The maximum of sensitivity at 295°К (2,0-2,8 microns) is adjusted under the order by change of thickness of a film from 0,3 to 0,65 microns. Our Photoconductive Detector PbS functions as ideal quantum counter in whole spectral response range under influence of the interference inside the film. The measurements of sensitivity to ultra-violet light are carried out up to 0,2 microns.

Measurements were carried out using radiators: “Blackbody” at 573 °K (+300°С),  the «A»-type light source (a heating lamp at 2840°К),
IR-diodes; the UV- light source (deuterium lamp).

* Superfast photoresistors PbS with a time constant 5-8 µs (D*~1×1010 sm W -1Hz0,5) and (14-20) µs (D*~2×1010 sm W -1Hz0,5) are offered, shift of spectral sensitivity to the right ( λmax=2,7 µm, λ0,5 = 3,0 µm) is possible.