| 摘要 |
<p>In a photocell of the photoelectric transducer having a compound semiconductor substrate (11), a photodiode (12) is doped with an impurity of a conductivity type opposite to that of the substrate (11). An enclosure region (13) is formed by the same doping as the photodiode (12), surrounding but apart from the photodiode (12). A gate electrode (15) is formed, on an insulation layer (14) formed all over the substrate surface (11), over a portion in-between the photodiode (12) and the enclosure region (13). The enclosure region (13) is connected via a contact hole (20) through the insulation layer (14) and a first switch (22) to a ground level. The gate electrode (15) is connected via a second switch (23) to a predetermined voltage having the same polarity as the conductivity type of the substrate (11). On a high-resolution mode, the first switch (22) is closed and the second switch (23) is open, so that the grounded enclosure prevents carrier generated in-between the photodiode (12) and the enclosure region (13) from flowing into an adjacent cell. On a high-sensitivity mode, the first switch (22) is open and the second switch (23) is closed, so that the gate voltage generates a channel to electrically connect the photodiode (12) to the enclosure region (13), thus the carriers generated within the enclosure (13) are all gathered to the photodiode (12). The first and second switches (22, 23) may be fabricated on a second semiconductor substrate (16) arranged over the compound semiconductor substrate (11), which is connected to the second substrate (16) via bumps (18, 18A, 18B). <IMAGE></p> |
