Fujitsu Corporation

Soichiro Hikida

Gen Sudo

Kenji Arinaga

Yuichiro Ito

Nobuyuki Kajihara

Koji Fujiwara

A semiconductor image pickup device comprises a photo-sensing substrate and a signal processing substrate, wherein the photo-sensing substrate further comprises a plurality of detector elements, and the signal processing substrate comprises a plurality of input diodes, each detector element being operatively connected to the respective input diode. The detector elements are isolated and light shielded from each other and further from the signal processing substrate by a light shield layer, and each detector element has an input port for incident rays on an input side of the photo-sensing substrate and has a surface region on the opposite side for outputting a signal to the input diode. The light shield layer of the invention comprises an insulation multilayer and a metal layer laminated in this order from the input side of the incident rays. The embodiments utilize a silicon nitride layer and zinc sulphide layer as the insulation multilayer.

Semiconductor infrared image pickup device and method of fabricating the

A method for fabricating a semiconductor image pickup device for detecting a light image includes a step of forming an array of detector elements, each of which generates an electronic signal in response to light incident thereto, and a step of forming a light absorbing layer which is situated to optically isolate each of the detector elements. The array of detector elements in the light absorbing layer can be formed on a substrate. In one embodiment, the light absorbing layer is produced by forming a first layer contacting with each of the detector elements which has a first refractive index, forming a second layer contacting with the first layer which has a second refractive index greater than the first refractive index of the first layer, and forming a metal layer contacting with the second layer. By forming the light absorbing layer in this manner, the array of detecting elements can be optically isolated from each other so that problems such as cross-talk, for example, can be reduced.

Method of fabricating a semiconductor image pickup device

A photoelectric transducer having a photocell includes a compound semiconductor substrate in which a photodiode is doped by an impurity of a conductivity type opposite to that of the substrate. An enclosure region is formed by the same doping impurity as the photodiode, surrounding but spaced apart from the photodiode. A gate electrode is formed on a portion of an insulation layer, the latter formed all over the substrate surface, which extends between the photodiode and the enclosure region. The enclosure region is selectively connected, via a contact hole through the insulation layer and a first switch to ground level. The gate electrode is connected via a second switch to a predetermined voltage having the same polarity as the conductivity type of the substrate. In a high-resolution mode, the first switch is closed and the second switch is open, so that the grounded enclosure region prevents carriers generated in the substrate, between the photodiode and the enclosure region, from flowing into an adjacent cell. In a high-sensitivity mode, the first switch is opened and the second switch is closed, so that the gate voltage generates a channel which electrically connects the photodiode to the enclosure region; thus, the carriers generated within the enclosure are all gathered to the photodiode. The first and second switches may be fabricated on a second semiconductor substrate, arranged parallel to but spaced from the compound semiconductor substrate and electrically connected thereto via bumps.

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Kawasaki, Japan

Soichiro Hikida