Light trigger and light quench static induction thyristor (LTLQ-SIThy) is described on the optical triggering and quenching mechanism. The static induction gate structure provides the high turn-on gain. Static induction photo transistor (SIPT) is used for the quenching device. The SIPT gives the high gain of the LTLQ-SIThy at turn-off. This functionally integrated power device provides the high efficiency to switch the large energy. The new LTLQ-SIThy which utilizes the LQ-SIThy for the quenching device is reported. This LTLQ-SIThy improves the switching ability in the large current, the dependency of temperature, and the controllability by the trigger/quench light.

We shall consider quantum-effect devices based on the resonant tunneling and charge-injection devices based on the real-space transfer. These devices can be operated at high speed and can perform complex and novel circuit functions with reduced component counts. Therefore, these devices will find important applications in future microelectronics.

The development of InSb staring image sensors is reviewed. Some necessary conditions to achieve the first imaging demonstration are described from semiconductor material, oxide insulator, device structure, and device operation aspects. The readout operation design by utilizing the InSb material properties is revealed. The progress since then is briefly presented. The future competitions and development directions are discussed.

Anodic sulfides were grown on HgCdTe using different electrolyte concentrations and current densities. These sulfide films were characterized by film thickness, refractive index, and composition depth profile. The results demonstrate a strong dependence of film properties on the extent of electrolyte polarization. By enhancing the polarization effect during anodization high quality sulfide/HgCdTe interfaces, and thus satisfactory electrical characteristics, are obtained.

A special one-dimensional position-sensitive device for detection of a light-spot location is designed and fabricated. The device is composed of a pair of photodiodes with complementarily interdigited comb configuration. The width of comb teeth is characterized by a designated distributive function, hence, the coordination information of a light spot falling upon the device can be determined by photo-induced currents of the two diodes. This device is useful as the position sensing element in camera-autofocus application.

A promising contact-type linear image sensor, 16 bit/mm high resolution Schottky a-Si:H photodiodes have been fabricated, and its temperature effect on I-V characteristics has been clarified. To achieve excellent small darkcurrent and improve Ip/Id ratio, the a-Si:H photodiodes with the passivation layer being annealed at 200 degree(s)C in air for 30 min is found essentially necessary. In the reverse bias mode, the darkcurrent increases with temperature and doubles for every 8.89 degree(s)C rise, while the photocurrent exhibits little affect below 100 degree(s)C.

The electrolyte electroreflectance and reflectivity measurements were used to study the etching process and analyze the etching mechanism of etched anodic oxide film on HgCdTe. The observed shift of the energy peak in reflectance spectrum can be explained by the surface roughness. It was found that the oxide etched by HCl or HNO3 does not recover the original reflectivity spectra due to the surface characteristics, but lactic acid does. The multiple reflection theory was used to calculate the thickness and the etching rate of the oxide film. The etching characteristics of lactic acid have also been studied for different concentrations.

Using in situ stress measurement combined with infrared spectra and high frequency capacitance-voltage measurement, water effects on the properties of sio2/PSG/sio2 passivation of InSb have been investigated during the passivation film exposure to air after high vacuum annealing. Water absorption in the film gives rise to a compressive stress, causes the flat-band of the film's capacitance-voltage curve to shift toward positive and assists ions to diffuse into the film. These show that water absorption in the porous structure of the passivating film can be the cause of the instability of the film's properties.

Staring FPA devices are coming to a state of performance and maturity. However, they are still the major defect source of the modernized E/O systems. MTF may act as a promising tool in evaluating their system requirements. Following a review of the MTF measurement technology, the evaluation of a PtSi Schottky-barrier FPA camera with one of the methods is given. It shows that a new MTF standard should be established when this type of test is applied to a discretely sampled staring array system. Current efforts have been made in our laboratory for this purpose. Detailed MTF results are presented for discussion, and we believe that it is necessary to include the CTF data at Nyquist ratio.

A high performance PtSi Schottky barrier sensor array was developed. It was fabricated by using a double-poly double-metal 2.0 micrometers Si-based technology and an ultra-high vacuum E-beam PtSi process. The barrier height of the Schottky barrier IR detector is 0.21 to 0.22 eV with 4nA/cm² dark current density at 77 degree(s)K. Its quantum efficiency is 0.3% at 4 micrometers . The charge handling capacity of the CCD is larger than 2.0E6 electrons/pixel. The charge transfer efficiency of the CCD at 77 degree(s)K is 0.9998 to 0.9999. The imaging capability of this chip to a thermal scene has been demonstrated.

An integrated a-Si:H linear image sensor with a TFT-type photoconductor was successfully demonstrated. Each sensor element of the linear image sensor consists of a TFT-type photoconductor, a storage capacitor, and two TFT switches. All the devices were fabricated simultaneously with the same metal-insulator-semiconductor structure used for the TFTs. The characteristics of the TFT-type photoconductor and the TFTs are measured. The operation principle of the image sensor array is described; and the dynamic testing of a sensor element is discussed.

The paper describes the tests performed on the enhanced thematic mapper (ETM) cold focal plane array (CFPA) after it was fully characterized in a test dewar and before the full instrument integration. The cold focal plane array was first integrated onto the radiative cooler with the thermal switch open so there is no thermal conduction between the radiator cold stage and the CFPA. A Joule-Thompson cooler was used to cool the CFPA during the before- and after-vibration tests. After these two bench-level tests the thermal switch was closed and the CFPA cooler assembly was prepared for the final thermal-vacuum chamber testing. This test encompasses two major goals. The first one is to make certain that the cooler performance meets specifications. This was done with the cooler facing a simulated cold space background and proper thermal loads were impressed. The second is to adjust the band 6 (PC HgCdTe) preamp circuits so maximum dynamic range can be realized during the actual flight environment. The work was performed while the author was affiliated with Santa Barbara Research Center.

In this paper, the systems and unique advantages for applying incoherent multimode fiber- optic bundles (MMBs) and coherent multimode image bundles to electronic speckle pattern interferometry (ESPI) are described. Fiber optics ESPI exhibits many advantages when compared to conventional ESPI. This study has shown that MMBs are much better than individual multimode fiber optic used in ESPI. By designing the structure of MMBs specially, we can adjust the number with any ratio for the object and reference beams in order to maximize the visibility of the ESPI fringes. Some other methods were used to improve the quality of the fringes. This paper also introduces a series of experiments which research the problems for applying MMBs ESPI to measure displacement, strain, and unbonded faults in the carbon/epoxy honeycomb components. All the experimental results agree well with the theory.

During two color sensor fusion it is found that an electric time delay and integration (TDI) circuit can be replaced by an equivalent optical TDI method. This contains a dichroic mirror to separate dual wavebands into two image focal planes with a two-dimensional image translation between the image focal planes. The experimental result shows that performance of the fusion sensor is improved with an increased video signal to noise ratio and a lower minimum resolvable temperature difference. It can also provide a real time (30 frames) single enhanced dual band thermal image.

An optical fiber PZT cylinder phase modulator is frequently used in an optical fiber interferometric sensor for demodulating sensing signals. In this paper, we combine the piezoelectric equations and the fiber phase shift relations to deliver a thorough description of the phase response of the optical fiber PZT cylinder phase modulator. We also design an experiment to verify our derivation. The result is quite compatible with published data.

A high accuracy optical bistable temperature sensor was proposed and proved experimentally by using a fiber-optic Mach-Zehnder interferometer combined with an electro-optic bistable device.

A new phase-reading detection method for signal processing in optical interferometric sensors is proposed and demonstrated. This method is based on a laser diode frequency modulated by a triangular waveform and time gating techniques. In our method, information on the optical phase can be extracted either from the beat frequency itself or the phase of the beat signal. The former would be used for displacement of the order of many wavelengths while the latter allows measurement in the subnanometer range. Detection of optical phase change as small as 2.0 X 10^-5rad/(root)Hz with excellent linearity is demonstrated. Other useful applications of this technique are also briefly discussed.

The phase error of polarization-maintaining fiber gyro due to the imperfect couplers and splices is considered. The results in a special case are consistent with that of previous authors. Experimentally observed bias stability agrees well with theoretical predictions.

Acousto-optic tunable filter (AOTF) is an electronically tuned optic filter that operates on the principle of acousto-optic diffraction. It consists of a birefringent crystal to which a piezoelectric transducer is bonded. The transducer converts the rf signal applied on it to acoustic wave, the acoustic wave launched into the crystal modulates the index of refraction of crystal periodically. This provides a moving phase grating which will diffract portions of incident light beam. For a fixed acoustic frequency, only a limited spectral band of incident light can approximately satisfy the phase-matching condition and be diffracted by the filter. The center of the band will change with the acoustic frequency, i.e., rf signal frequency. Thus a spectral filter is created. AOTF has advantages of wide tuning range, high spectral resolution, large angular aperture, and fast scan rate. These advantages make AOTF attractive for a variety of applications.

This study concentrates on using multimode and singlemode fiber in electronic speckle pattern interferometry (ESPI) to measure deformation and nondestructive testing. The advantages and disadvantages of singlemode versus multimode fiber optic components are discussed. Several experiments which research the problems of applying fiber optics to ESPI for measuring displacement, unbonded faults in the carbon/epoxy honeycomb components are introduced. A series of methods were used to achieve good contrast interference fringes. All the experimental results agree well with the theory.

Multitemporal measurements in ten discrete spectral bands in the range from 0.4 to 1.0 micron have been carried out with the help of the indigenously developed spectro-polarimeter. The measurements have been carried out under minimum haze sky conditions twice a week in a period of about 100 days. In-band exoatmospheric solar spectral irradiance values for the corresponding sun angles have been computed from the standard available data. The values have been corrected for sun-earth distance and the atmospheric transmittances from space to ground have been estimated. This estimation has been compared with the AFGL LOWTRAN 6 atmospheric model. This exercise would be useful to support/verify existing theoretical models and practical measurements. Additionally, it could be useful to interpolate global ground irradiance with maximum radiometric uncertainties of 11%. This paper describes the experimental details and some of the results obtained.

The paper describes a new pressure sensor made of piezoresistive material, simple in structure, easy to operate, and lower in cost which may greatly increase positioning accuracy and sensitivity. This sensor is applied to the laboratory of universities or institutes. We give an example of robot assembling in this paper.

Narrowband self-filtering GaAs photodiode has been fabricated by LPE growth. N-type epitaxial layers of hi-lo-hi structure were grown on P-type substrate. By properly controlling the thickness and the doping concentration of the epilayers efficient blue suppression of the detector response is achievable, with a bandwidth as narrow as 315 angstroms centered at 880 nm. The device, therefore, is very useful in many applications which require background suppression and spectral matching to the correspondent LED light source.

Sensitivity enhancement in fiber interferometric sensors is achieved by connecting a balanced nonlinear Mach-Zehnder fiber interferometer (MZFI) to the sensing interferometer. Without changing the power of the source, the sensitivity is enhanced by a factor of nonlinear phase shift induced by the optical power in the nonlinear MZFI. The theory is also extended to remote fiber sensing systems.

The passivation of HgCdTe plays an important role in determining its device performance. Because of the extreme temperature sensitivity of the HgCdTe, we constrain deposition processes within 90 degree(s)C. Three different kinds of passivation layers (SiO₂, ZnS, native oxide/ZnS) have been studied and compared in this paper. The AES is used to evaluate the composition. The C-V curve of MIS capacitor and I-V curve of P-N junction diode are used to characterize the electrical properties of these passivation layers. We have successfully grown an excellent SiO₂ layer by the direct photo-CVD method at 70 degree(s)C, which makes the R_oA of HgCdTe photovoltaic diode to be as high as 5 X 10⁵ ohm- cm² at 77 degree(s)K.

This paper describes processing methods and test results on single crystal indium antimonide (InSb) charge injection device (CID) focal plane arrays (FPAs) with SiO₂ made by (1) radio frequency heated chemical vapor deposition (rf CVD); or (2) photoactivated CVD (PACVD). Processing details are more detailed than previously revealed. Related process testing is also discussed.