The authors report the design, growth, fabrication, and characterization of a low-strain quantum dots-in-a-well (DWELL) infrared photodetector. This novel DWELL design minimizes the inclusion of the lattice-mismatched indium-containing compounds while maximizing the absorption cross section by enabling larger active region volume. The improved structure uses an In0.15Ga0.85As/GaAs double well structure with Al0.10Ga0.90As as the barrier. Each layer in the active region was optimized for device performance. Detector structures grown using molecular beam epitaxy were processed and characterized. This new design offers high responsivity of 3.9 A/W at a bias of 2.2 V and a detectivity of 3x10(9) Jones at a bias of 2.2 V for a wavelength of 8.9 mu m. These detectors offer significant improvement in the responsivity while retaining the long wave infrared spectral properties of the InAs/In0.15Ga0.85As/GaAs DWELL. These detectors if coupled with improved noise characteristics could enable higher temperature operation of DWELL detectors, thus reducing the dependence on cooling equipment. (C) 2008 American Vacuum Society.