Since authors have successfully demonstrated uncooled infrared (IR) focal plane array (FPA) with 23.5 um pixel
pitch, it has been widely utilized for commercial applications such as thermography, security camera and so on. One of
the key issues for uncooled IR detector technology is to shrink the pixel size. The smaller the pixel pitch, the more the IR
camera products become compact and the less cost. This paper proposes a new pixel structure with a diaphragm and
beams which are placed in different level, to realize an uncooled IRFPA with smaller pixel pitch )≤17 μm). The upper
level consists of diaphragm with VOx bolometer and IR absorber layers, while the lower level consists of the two beams,
which are designed to place on the adjacent pixels.
The test devices of this pixel design with 12 um, 15 um and 17 um pitch have been fabricated on the Si ROIC of
QVGA (320 × 240) with 23.5 um pitch. Their performances reveal nearly equal to the IRFPA with 23.5 um pitch. For
example, noise equivalent temperature difference (NETD) of 12 μm pixel is 63.1 mK with thermal time constant of 14.5
msec. In addition, this new structure is expected to be more effective for the existing IRFPA with 23.5 um pitch in order
to improve the IR responsivity.