The electrical properties in highly doped, weakly strained (In,Ga)(As,N)/(Al,Ga)As MQWs are studied by Hall measurements at various temperatures. With increasing N content in the well and Al content in the barrier, the electron mobility is strongly reduced. Magnetoresistance measurements are performed at low temperatures revealing carrier localization induced by the incorporation of N. From Raman spectroscopy, a preferential incorporation of N at the interface with the (AI,Ga)As barrier is found. Intersubband absorption experiments show only a small shift of the signal with increasing N content, but a strongly reduced and broadened absorption peak. © 2005 Elsevier B.V. All rights reserved.