  Building on the successful development of the 10 $\mu m$ HgCdTe detector
arrays for the proposed NEOCam mission, the University of Rochester Infrared
Detector team and Teledyne Imaging Systems are working together to extend the
cutoff wavelength of HgCdTe detector arrays initially to 13 $\mu m$, with the
ultimate goal of developing 15 $\mu m$ HgCdTe detector arrays for space and
ground-based astronomy. The advantage of HgCdTe detector arrays is that they
can operate at higher temperatures than the currently used arsenic doped
silicon detector arrays at the longer wavelengths. Our infrared detector team
at the University of Rochester has received and tested four 13 $\mu m$ detector
arrays from Teledyne Imaging Systems with three different pixel designs, two of
which are meant to reduce quantum tunneling dark current. The pixel design of
one of these arrays has mitigated the effects of quantum tunneling dark
currents for which we have been able to achieve, at a temperature of 28 K and
applied bias of 350 mV, a well depth of at least 75 $ke^-$ for 90% of the
pixels with a median dark current of 1.8 $e^-/sec$. These arrays have
demonstrated encouraging results as we move forward to extending the cutoff
wavelength to 15 $\mu m$.
