Photovoltaic Mercury Cadmium Telluride Detectors

Transcription

1 Photovoltaic Mercury Cadmium Telluride s Teledyne Judson Technologies LLC Commerce Drive Montgomeryville, PA 89 USA Tel: -8-9 Fax: --7 Visit us on the web. ISO 9 Certified /

2 J9 PV MCT Operating Notes (. to. µm) General.E+.E+ -9C D* (Jones) J9 series detectors are high-quality HgCdTe (MCT) photodiodes for use in the nm to.µm spectral range. The equivalent circuit is a photon-generated current source Iph with parallel capacitance CD, shunt resistance RD, and series resistance RS. (Figure ) Figure ical D* vs Wavelength for room temperature and TE-, PV MCT,.8µm cutoff, mm, 8 FOV; FOV at -9C Figure Photodiode Equivalent Circuit -8C.E+ -C -C -C.E+ C.E Wavelength (um) Responsivity Cooling an MCT photodiode increases its shunt resistance which results in reduced noise and improved detectivity. Figures and show the relationship between detector temperature and detectivity (D*) as a function of wavelength. The D* plots in Figure are for a detector with an active size of mm, % cutoff wavelength at µm and operating from -C to -9C. The detectors are mounted on thermoelectric coolers (TEC) where one-stage (TE) is used for -C operation and subsequent stages (TE, TE and TE) are used to achieve lower temperatures. Similarly, Figure shows a series of plots for D* vs. wavelength for a detector with an active size of mm, % cutoff wavelength at.8µm and operating from room temperature (+C) to -9C. The field of view (FOV) is 8 except at -9C where the FOV is. Figure ical Spectral Response, PV MCT, µm cutoff, mm, TE-, 8 FOV..7. Responsivity (A/W) Temperature Effects Figures and show a typical spectral response for mm size, µm and.8µm cutoff, respectively. Please refer to Tables, and for further detector specifications for.8µm, µm and.µm wavelength cutoffs, respectively Wavelength Figure ical D* vs Wavelength for TE-, PV MCT, µm cutoff, mm, 8 FOV, -9C Figure ical Spectral Response, PV MCT,.8µm cutoff, mm, 8 FOV.E+.. Responsivity (A/W) D* (Jones) -9C -8C.E+ -C.9. -C. -C.E+9 Wavelength..... Wavelength (um) /

3 Thermoelectric Cooler Operation Advantages of Photovoltaic MCT Teledyne Judson offers a variety of convenient packages for room temperature and thermoelectrically (TE) cooled operation. ical power requirements for the TE, TE and TE coolers are shown in Figures 8, 9 and on page. The built in thermistor can be used to monitor or control the temperature. Figure shows typical thermistor resistance vs. temperature values. Sensitivity and cutoff wavelength are functions of temperature. temperature should be optimized for a particular application. Unlike the MCT photoconductors commonly used in the 7nm to.µm region, MCT photodiodes operate in the photovoltaic mode and can operate at zero bias. J9 detectors are a better choice for DC and low-frequency applications as they exhibit low /F noise characteristics as compared to PbS, PbSe and HgCdTe photoconductors. J9 detectors also offer superior pulse response for applications in monitoring and detecting high-speed pulsed lasers. They do not require a chopper and exhibit better linearity than photoconductive detectors. Figure ical Thermistor Curve Accessories Thermistor Resistance (K ) A thermoelectrically cooled detector requires a heat sink to dissipate the heat generated by the cooler, an amplifier to amplify the detector signal to a usable level and a temperature controller to hold the detector at a constant temperature. Teledyne Judson TE cooler accessories are designed to provide solutions for our customers. The CMAMP series is designed for customers that would like a fully integrated detector module. It includes heatsinking, detector signal amplification and temperature control. We also offer heat sink assemblies without preamps or temperature controllers. Please ask customer service for Product Bulletin PB for more information. Operating Circuit The recommended operating circuit for most applications is an operational amplifier in a negative-feedback transimpedance configuration (Figure 7) with up to.v reverse bias put across the detector. This reverse bias will increase the effective shunt impedance of the detector but will also increase the detector /F noise. Figure 7 ical Operating Circuit RF < V IDARK IS - Cooler / Preamplifier Recommendations Shunt Impedance Recommended Cooler Module Part to K CMAMP-TO-PA-LZ CMAMP-CN-PA-LZ 9 9 > K CMAMP-TO-PA-HZ CMAMP-CN-PA-HZ CMAMP assembly includes heat sink, temperature controller and transimpedance amplifier for the J9TE packages. Vo = IS RF + Isc Vos /

4 Table..8µm Cutoff Room Temperature and Thermoelectrically Cooled PV MCT, One Through Four Stages (TE-) Shunt impedence Active Size Operating % Cutoff (Ohm) Diameter Temp. Wavelength Wavelength Responsivity Part (A/W) (mm) ( C) Model J9:.8-8C-RU J9:.8-8C-RM J9TE:.8-C-RU J9TE:.8-C-RM J9TE:.8-C-RU J9TE:.8-C-RM J9TE:.8-C-RU J9TE:.8-C-RM J9TE:.8-CN-RU J9TE:.8-CN-RM J9TE:.8-VN-RU J9TE:.8-VN-RM TBA TBA E+ 7.E+.E+.E+ 7.E+ 7.E+.E+.E+.E+7.E+.E+7.E+.E+.E+.E+.E+.E+.E+ 8.E+ 8.E+.E+7.E+.E+7.E+ Dark -.V (A) Max.E-.E-.E-7.E-.E-8.E-7.E-9.E-8.E-9.E-8.E-9.E-8.E-.E-.E-.E-.E-7.E-.E-8.E-7.E-8.E-7.E-8.E-7 D* KHz.E+.E+ 7.7E+ 9.7E+.E+.7E+.7E+.9E+ 7.E+ 9.E+ 8.E+.E+.8E+.E+.E+.E+.9E+.7E+.9E+ 7.E+ 8.E+.E+ 8.E+.E+ All specs are for detector operation at V bias and 8 FOV unless otherwise specified. Maximum reverse bias voltage for all detectors is.v. Table..µm Cutoff Thermoelectrically Cooled PV MCT, One Through Four Stages (TE-) Model J9TE:-C-RU J9TE:-C-RM J9TE:-C-RU J9TE:-C-RM J9TE:-C-RU J9TE:-C-RM J9TE:-CN-RU J9TE:-CN-RM * J9TE:-VN-RU * J9TE:-VN-RM Shunt impedence Active Size Operating % Cutoff (Ohm) Diameter Temp. Wavelength Wavelength Responsivity Part.. (A/W) (mm) ( C) E+.E+.E+.E+.E+.E+.E+.E+.E+.E+.E+.E+.E+.E+.E+.E+ 7.E+ 7.E+.E+.E+ Dark -.V (A) Max.E-.E-.E-.E-.E-.E-.E-.E-.E-.E-.E-.E- 8.E- 8.E-.E-.E-.E-.E- 8.E- 8.E- D* KHz.E+9.E+9 7.E+9 7.E+9.E+.7E+.7E+.E+.8E+.8E+.E+9.7E+9.E+.E+.E+.E+.8E+.E+.E+.8E+ All specs are for detector operation at V bias and 8 FOV unless otherwise specified. * FOV. Maximum reverse bias voltage for all detectors is.v. Higher responsivity may be achieved at reverse bias. Table..µm Cutoff Thermoelectrically Cooled PV MCT, One Through Four Stages (TE-) Model Active Size Operating % Cutoff Diameter Temp. Wavelength Wavelength Responsivity Part.. (A/W) (mm) ( C) J9TE:.-C-RU J9TE:.-C-RM J9TE:.-C-RU 8 J9TE:.-C-RM 9 J9TE:.-C-RU J9TE:.-C-RM J9TE:.-CN-RU J9TE:.-CN-RM * J9TE:.-VN-RU * J9TE:.-VN-RM 9 All specs are for detector operation at Maximum reverse bias voltage for all Shunt impedence (Ohm) E+.E E+.E E+.E E+.E E+.E E+.E E+.E E+.E E+.E E+.E+ V bias and 8 FOV unless otherwise specified. * FOV. detectors is.v. Higher responsivity may be achieved at reverse bias. Dark -.V (A) Max.E-.E-.E-.E-.E-.E-.E-.E-.E-.E-.E-.E-.E-.E-.8E-.8E-.E-.E-.E-.E- D* KHz.E+9.8E+9.9E+9.9E+9.E+.E+.E+.E+.9E+.7E+.E+9.E+9 8.E+9 8.E+9.7E+.9E+.E+.E+.E+.E+ /

5 C/D Package CN Package. Thk AR Coated Sapphire Window. MAX. Top, Sealant. DIA.. Dia.. Clear Aperture Outer, Top Cap C: AR Coated Sapphire Window D: Sapphire Window. SQ.7 DIA. REF. Sealant.7 TYP Top,.. ±. MAX.8 ±..9 ± REF. 7 Side View Pin No. Designation Sleeve Color Thermistor Cathode (-) White Yellow Anode (+) Green Cooler (-) Black Cooler (+) Red N/C Clear 7 N/C Clear 8 Thermistor Yellow 7S Package 8C Package Figure 8 Temperature vs TE Cooler Current Figure 9 Temperature vs TE Cooler Current Figure Temperature vs TE Cooler Current /

6 In addition to our Photovoltaic MCT product line, Teledyne Judson Technologies offers a wide range of high performance standard, custom and space qualified detector products and accessories. Germanium detectors and arrays Indium Arsenide detectors and arrays Indium Antimonide detectors and arrays Mercury Cadmium Telluride detectors and arrays Lead Selenide detectors and arrays Lead Sulfide detectors and arrays Dewars, backfill and vacuum packages Thermoelectric, Joule Thomson and closed cycle linear and rotary coolers Preamplifiers Temperature controllers and readout electronics Please contact us for more information on these products at -8-9 or on the web at Commerce Drive Montgomeryville, PA 89 USA Tel: -8-9, Fax: November, /