Articles you may be interested inActive-matrix Spindt-type field emitter array with faster response time for image sensor with high-gain avalanche rushing amorphous photoconductor target J. Vac. Sci. Technol. B 33, 012205 (2015); 10.1116/1.4906103 2 ∕ 3 in. ultrahigh-sensitivity image sensor with active-matrix high-efficiency electron emission device J. Vac. Sci. Technol. B 28, C2D11 (2010); 10.1116/1.3271163 640 × 480 pixel active-matrix Spindt-type field emitter array image sensor with high-gain avalanche rushing amorphous photoconductor target J. Vac. Sci. Technol. B 28, 96 (2010); 10.1116/1.3272732Enhanced output current density of an active-matrix high-efficiency electron emission device array with 13.75 μ m pixels An extremely high-sensitivity image sensor has been developed with a combination of an active-matrix high-efficiency electron emission device ͑HEED͒ array and a high-gain avalanche rushing amorphous photoconductor ͑HARP͒ target. Following the description of the requirements for the use of the electron emitter as an image-sensing probe, the characteristics of a fabricated 640ϫ 480 pixel active-matrix HEED image sensor with a HARP target are presented by image-pickup experiments under a dark condition. The emission current density of the experimental HEED under an active-matrix drive was 4 A / cm 2 corresponding to a practical level. A clear image observed in the prototype compact camera demonstrates that the surface-emitting HEED is useful for image sensing based on HARP with high sensitivity and sufficient definition.

A 640×480pixel image sensor has been developed for low light imaging with a practical resolution. This image sensor combined an active-matrix high-efficiency electron emission device (HEED) with a high-gain avalanche rushing amorphous photoconductor (HARP) target. To meet the requirement for a scaling of the imaging size, we developed a 2∕3in. image sensor based on an active-matrix HEED with 13.75×13.75μm2pixels. The highly emissive property of 3.8μA∕pixel was comparable to that obtained previously from a 1in. device. The possible effect of the pixel size scaling on the image-pickup sensitivity was compensated by a significant increase in the emission current density. The technological potential of the HEED-HARP image sensing has been further enhanced toward practical use.

Articles you may be interested inActive-matrix Spindt-type field emitter array with faster response time for image sensor with high-gain avalanche rushing amorphous photoconductor target J. Vac. Sci. Technol. B 33, 012205 (2015); 10.1116/1.4906103 2 ∕ 3 in. ultrahigh-sensitivity image sensor with active-matrix high-efficiency electron emission device J. Vac. Sci. Technol. B 28, C2D11 (2010); 10.1116/1.3271163 640 × 480 pixel active-matrix Spindt-type field emitter array image sensor with high-gain avalanche rushing amorphous photoconductor target Development of a super-high-sensitivity image sensor using 640 × 480 pixel active-matrix high-efficiency electron emission device An active-matrix array of high-efficiency electron emission device ͑HEED͒ with a sufficient output density has been developed for the use as imaging probe in a high-gain avalanche rushing amorphous photoconductor target. Previously, it was demonstrated that a prototyped image sensor with 20ϫ 20 m 2 pixels could pick up a high definition image with an ultrahigh sensitivity under low-light-level condition. Based on it, an efficient active-matrix HEED with 13.75 ϫ 13.75 m 2 pixels is fabricated for pursuing higher sensitivity and resolution. The improvement in the device isolation method enables to enlarge the relative emitting area, and then the emission current density per pixel reaches 3.6 A / cm 2 that is about four times of that obtained from the previous one. The active-matrix HEED array with small pixels is available for application to the compact ultrahigh-sensitivity image sensor without affecting on the image definition.

Articles you may be interested inActive-matrix Spindt-type field emitter array with faster response time for image sensor with high-gain avalanche rushing amorphous photoconductor target J. Vac. Sci. Technol. B 33, 012205 (2015); 10.1116/1.4906103 2 ∕ 3 in. ultrahigh-sensitivity image sensor with active-matrix high-efficiency electron emission device J. Vac. Sci. Technol. B 28, C2D11 (2010); 10.1116/1.3271163 640 × 480 pixel active-matrix Spindt-type field emitter array image sensor with high-gain avalanche rushing amorphous photoconductor target J. Vac. Sci. Technol. B 28, 96 (2010); 10.1116/1.3272732Enhanced output current density of an active-matrix high-efficiency electron emission device array with 13.75 μ m pixels Development of a super-high-sensitivity image sensor using 640 × 480 pixel active-matrix high-efficiency electron emission device An image sensor consisting of an active-matrix high-efficiency electron emission device ͑HEED͒ array and a high-gain avalanche rushing amorphous photoconductor ͑HARP͒ has been fabricated. Based on the demonstration that a prototyped 256ϫ 192 pixel image sensor can pick up a high definition image with an ultrahigh sensitivity under poor light condition, the authors have been developing a 640ϫ 480 pixel active-matrix HEED toward a practical use. The emission current density has been enhanced more than twice compared to that of previous one and has increased up to 1 A/cm 2 . The active-matrix HEED array combined with HARP is available for application to practical image sensing with an ultrahigh sensitivity and high definition.

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