We describe the design, gas-source MBE growth, and performance of a highly strained photovoltaic intersubband detector with peak responsivity between 3 and 4 mu m. The absorbing region is composed of a highly strained InGaAs-InAs-InAlAs-AlAs heterostructure with its average lattice constant matched to InP. The detector design is based on a combination of bound-to-bound and bound-to-continuum transitions, which together allow a broad-band photoresponse, comparable to that of detectors with heterogeneous absorption region. (c) 2013 Elsevier B.V. All rights reserved.