Processing of nano boron carbide reinforced flexible polymer composites with improved shielding properties

Aims: The main objective of the current research is to develop light-weight and flexible electromagnetic shielding materials with improved properties using nano/mikro boron carbide dispersed into polymer based matrices after surface modification. Methods: Nano/micro boron carbide particles with various morphologies were synthesized by sol-gel techniques and the obtained particles were surface modified with different functional groups. After mixing the particles with different polymers using high shear mixer, shielding composite plates were shaped using injection moulding and warm pressing. Results: It was shown that sol-gel technique was able to produce boron carbide particles with controlled morphology and better shielding properties could be obtained using these particles within polymeric matrices leading to the formation of flexible composites. Conclusions: Overall, it was found that light-weight and effective shielding materials could be obtained using boron carbide particles dispersed within polymeric matrices. Surface modification of the particles is critical for good dispersion and hence to get better final properties. The concentration of the reinforcing particles also affects the properties in terms of energy absorption and shielding

Antileishmanial effect of silver nanoparticles and their enhanced antiparasitic activity under ultraviolet light

Leishmaniasis is a protozoan vector-borne disease and is one of the biggest health problems of the world. Antileishmanial drugs have disadvantages such as toxicity and the recent development of resistance. One of the best-known mechanisms of the antibacterial effects of silver nanoparticles (Ag-NPs) is the production of reactive oxygen species to which Leishmania parasites are very sensitive. So far no information about the effects of Ag-NPs on Leishmania tropica parasites, the causative agent of leishmaniasis, exists in the literature. The aim of this study was to investigate the effects of Ag-NPs on biological parameters of L. tropica such as morphology, metabolic activity, proliferation, infectivity, and survival in host cells, in vitro. Consequently, parasite morphology and infectivity were impaired in comparison with the control. Also, enhanced effects of Ag-NPs were demonstrated on the morphology and infectivity of parasites under ultraviolet (UV) light. Ag-NPs demonstrated significant antileishmanial effects by inhibiting the proliferation and metabolic activity of promastigotes by 1.5- to threefold, respectively, in the dark, and 2- to 6.5-fold, respectively, under UV light. Of note, Ag-NPs inhibited the survival of amastigotes in host cells, and this effect was more significant in the presence of UV light. Thus, for the first time the antileishmanial effects of Ag-NPs on L. tropica parasites were demonstrated along with the enhanced antimicrobial activity of Ag-NPs under UV light. Determination of the antileishmanial effects of Ag-NPs is very important for the further development of new compounds containing nanoparticles in leishmaniasis treatment

MT3825BA: A 384x288-25 mu m ROIC for Uncooled Microbolometer FPAs

This paper reports the development of a new microbolometer Readout Integrated Circuit (ROIC) called MT3825BA. It has a format of 384 x 288 and a pixel pitch of 25 mu m. MT3825BA is Mikro-Tasarim's second microbolometer ROIC product, which is developed specifically for resistive surface micro-machined microbolometer detector arrays using high-TCR pixel materials, such as VOx and a-Si. MT3825BA has a system-on-chip architecture, where all the timing, biasing, and pixel non-uniformity correction (NUC) operations in the ROIC are applied using on-chip circuitry simplifying the use and system integration of this ROIC. The ROIC is designed to support pixel resistance values ranging from 30 K Omega to 100 K Omega. MT3825BA is operated using conventional row based readout method, where pixels in the array are read out in a row-by-row basis, where the applied bias for each pixel in a given row is updated at the beginning of each line period according to the applied line based NUC data. The NUC data is applied continuously in a row-by-row basis using the serial programming interface, which is also used to program user configurable features of the ROIC, such as readout gain, integration time, and number of analog video outputs. MT3825BA has a total of 4 analog video outputs and 2 analog reference outputs, placed at the top and bottom of the ROIC, which can be programmed to operate in the 1, 2, and 4-output modes, supporting frames rates well above 60 fps at a 3 MHz pixel output rate. The pixels in the array are read out with respect to reference pixels implemented above and below actual array pixels. The bias voltage of the pixels can be programmed over a 1.0 V range to compensate for the changes in the detector resistance values due to the variations coming from the manufacturing process or changes in the operating temperature. The ROIC has an on-chip integrated temperature sensor with a sensitivity of better than 5 mV/K, and the output of the temperature sensor can be read out the output as part of the analog video stream. MT3825BA can be used to build a microbolometer FPAs with an NETD value below 100 mK using a microbolometer detector array fabrication technology with a detector resistance value up to 100 K Omega, a high TCR value (>2 % /K), and a sufficiently low pixel thermal conductance (G(th) <= 20 nW / K). MT3825BA measures 13.0 mm x 13.5 mm and is fabricated on 200 mm CMOS wafers. The microbolometer ROIC wafers are engineered to have flat surface finish to simplify the wafer level detector fabrication and wafer level vacuum packaging (WLVP). The ROIC runs on 3.3 V analog and 1.8 V digital supplies, and dissipates less than 85 mW in the 2-output mode at 30 fps. Mikro-Tasarim provides tested ROIC wafers and offers compact test electronics and software for its ROIC customers to shorten their FPA and camera development cycles

MT3825BA: a 384×288-25µm ROIC for uncooled microbolometer FPAs

This paper reports the development of a new microbolometer Readout Integrated Circuit (ROIC) called MT3825BA. It has a format of 384 x 288 and a pixel pitch of 25 mu m. MT3825BA is Mikro-Tasarim's second microbolometer ROIC product, which is developed specifically for resistive surface micro-machined microbolometer detector arrays using high-TCR pixel materials, such as VOx and a-Si. MT3825BA has a system-on-chip architecture, where all the timing, biasing, and pixel non-uniformity correction (NUC) operations in the ROIC are applied using on-chip circuitry simplifying the use and system integration of this ROIC. The ROIC is designed to support pixel resistance values ranging from 30 K Omega to 100 K Omega. MT3825BA is operated using conventional row based readout method, where pixels in the array are read out in a row-by-row basis, where the applied bias for each pixel in a given row is updated at the beginning of each line period according to the applied line based NUC data. The NUC data is applied continuously in a row-by-row basis using the serial programming interface, which is also used to program user configurable features of the ROIC, such as readout gain, integration time, and number of analog video outputs. MT3825BA has a total of 4 analog video outputs and 2 analog reference outputs, placed at the top and bottom of the ROIC, which can be programmed to operate in the 1, 2, and 4-output modes, supporting frames rates well above 60 fps at a 3 MHz pixel output rate. The pixels in the array are read out with respect to reference pixels implemented above and below actual array pixels. The bias voltage of the pixels can be programmed over a 1.0 V range to compensate for the changes in the detector resistance values due to the variations coming from the manufacturing process or changes in the operating temperature. The ROIC has an on-chip integrated temperature sensor with a sensitivity of better than 5 mV/K, and the output of the temperature sensor can be read out the output as part of the analog video stream. MT3825BA can be used to build a microbolometer FPAs with an NETD value below 100 mK using a microbolometer detector array fabrication technology with a detector resistance value up to 100 K Omega, a high TCR value (>2 % /K), and a sufficiently low pixel thermal conductance (G(th) <= 20 nW / K). MT3825BA measures 13.0 mm x 13.5 mm and is fabricated on 200 mm CMOS wafers. The microbolometer ROIC wafers are engineered to have flat surface finish to simplify the wafer level detector fabrication and wafer level vacuum packaging (WLVP). The ROIC runs on 3.3 V analog and 1.8 V digital supplies, and dissipates less than 85 mW in the 2-output mode at 30 fps. Mikro-Tasarim provides tested ROIC wafers and offers compact test electronics and software for its ROIC customers to shorten their FPA and camera development cycles

A 1280x1024-15 mu m CTIA ROIC for SWIR FPAs

This paper reports the development of a new SXGA format low-noise CTIA ROIC (MT12815CA-3G) suitable for mega-pixel SWIR InGaAs detector arrays for low-light imaging applications. MT12815CA-3G is the first mega-pixel standard ROIC product from Mikro-Tasarim, which is a fabless semiconductor company specialized in the development of ROICs and ASICs for visible and infrared hybrid imaging sensors. MT12815CA-3G is a low-noise snapshot mega-pixel CTIA ROIC, has a format of 1280 x 1024 (SXGA) and pixel pitch of 15 mu m. MT12815CA-3G has been developed with the system-on-chip architecture in mind, where all the timing and biasing for this ROIC are generated on-chip without requiring any special external inputs. MT12815CA-3G is a highly configurable ROIC with many features that can be programmed through a 3-wire serial interface allowing on-the-fly configuration the ROIC. It performs snapshot operation both using Integrate-Then-Read (ITR) and Integrate-While-Read (IWR) modes. The CTIA type pixel input circuitry has 3 gain modes with programmable full-well-capacity (FWC) values of 10K e-, 20K e-, and 350K e- in the very high gain (VHG), high-gain (HG), and low-gain (LG) modes, respectively. MT12815CA-3G has an input referred noise level of less than 5 e-in the very high gain (VHG) mode, suitable for very low-noise SWIR imaging applications. MT12815CA-3G has 8 analog video outputs that can be programmed in 8, 4, or 2-output modes with a selectable analog reference for pseudo-differential operation. The ROIC runs at 10 MHz and supports frame rate values up to 55 fps in the 8-output mode. The integration time of the ROIC can be programmed up to 1s in steps of 0.1 mu s. The ROIC uses 3.3 V and 1.8V supply voltages and dissipates less than 350 mW in the 4-output mode. MT12815CA-3G is fabricated using a modern mixed-signal CMOS process on 200 mm CMOS wafers, and there are 44 ROIC parts per wafer. The probe tests show that the die yield is higher than 70%, which corresponds to more than 30 working ROIC parts per wafer typically. MT12815CA-3G ROIC is available as tested wafers or dies, where a detailed test report and wafer map are provided for each wafer. A compact USB 3.0 based test camera and imaging software are also available for the customers to test and evaluate the imaging performance of SWIR sensors built using MT12815CA-3G ROICs. Mikro-Tasarim has also recently developed a programmable mixed-signal application specific integrated circuit (ASIC), called MTAS1410X8, which is designed to perform ROIC driving and digitization functions for ROICs with analog outputs, such as MT12815CA-3G and MT6415CA ROIC products of Mikro-Tasarim. MTAS1410X8 has 8 simultaneously working 14-bit analog-to-digital converters (ADCs) with integrated programmable gain amplifiers (PGAs), video input buffers, programmable controller, and high-speed digital video interface supporting various formats including Camera Link. MT12815CA-3G ROIC together with MTAS1410X8 ASIC can be used to develop low-noise high-resolution SWIR imaging sensors with low power dissipation and reduced board area for the camera electronics

A 640x480-17 mu m ROIC for uncooled microbolometer FPAs

This paper reports the development of a new microbolometer Readout Integrated Circuit (ROTC), called MT6417BA. It has a format of 640 x 480 (VGA) and a pixel pitch of 171am. MT6417BA is Mikro-Tasarim's third microbolometer ROTC, which is developed specifically for surface micro-machined microbolometer detector arrays using high-TCR pixel materials, such as VO,, and a-Si. MT6417BA has a system-on-chip architecture, where all the timing, biasing, and pixel non-uniformity-correction (NUC) operations in the ROTC are applied using on-chip circuitry simplifying the use and system integration of this ROTC. MT6417BA has a serial programming interface that can be used to configure the programmable ROTC features and to load the NUC date to the ROTC. MT6417BA has a total of 4 analog video outputs and 2 analog reference outputs, placed at the top and bottom of the ROTC, which can be programmed to operate in the 1, 2, and 4-output modes and can support frames rates above 60 fps at 10 MHz pixel output rate. The ROTC is designed to support pixel resistance values ranging up to 100ka MT6417BA is operated using conventional row based readout method, where pixels in the array are readout in a row-by-row basis, where they are biased and integrated using synchronously applied NUC data. The NUC data is applied continuously in a row-by-row basis using the serial programming interface operated at 20 MHz supporting frame rates as high as 60 fps. The bias voltage of the pixels can be programmed over a 1.0 V range to compensate for the changes in the detector resistance values due to the variations coming from the manufacturing process. The ROTC has an on-chip integrated temperature sensor with a sensitivity of better than 5 mV / K, and the output of the temperature sensor is embedded in the analog video stream. MT6417BA can be used to build a microbolometer FPAs with an NETD value below 50 mK using a microbolometer detector array fabrication technology with a nominal detector resistance of 60 Kf2, a high TCR value (>3 % / K), and a sufficiently low pixel thermal conductance (Gth < 10 nW / K). MT6417BA ROTC die measures 14.1 mm x 15.4 mm in a 180 nm CMOS. MT6417BA is fabricated on 200 mm diameter CMOS wafers with 100 parts per wafer. The microbolometer ROTC wafers are engineered to have flat surface finish to simplify the wafer level detector fabrication and wafer-level vacuum packaging (WLVP). The ROTC runs on 3.3 V analog and 1.8 V digital supplies, and dissipates less than 150 mW in the 2-output mode at 60 fps. Mikro-Tasarim provides tested ROTC wafers and offers compact test electronics and software for its ROTC customers to shorten their uncooled FPA and camera development cycles. Mikro-Tasarim has also recently developed a new programmable mixed-signal application specific integrated circuit (ASIC), called MTAS1410X4, which is designed to perform ROTC driving and digitization functions for microbolometer ROICs with analog outputs, such as MT6417BA and MT3825BA ROTC products of Mikro-Tasarim. MTAS1410X4 has 4 simultaneously working 14-bit analog-to-digital converters (ADCs) with integrated programmable gain amplifiers (PGAs), video input buffers, a programmable controller, and a flash memory interface for NUC operations. MT6417BA ROTC together with MTAS1410X4 ASIC can be used to develop low-noise and low-power uncooled microbolometer imaging sensors with compact camera electronics