The effects of well widths and well numbers of InGaAs triangular quantum well lasers in 2.30-2.44 mu m range using antimony-free material system on InP substrates are investigated. The triangular quantum well was equivalently formed by using gas source molecular beam epitaxy grown InAs/In053Ga0.47As digital alloy and the pseudomorphic growth was confirmed by the X-ray diffraction measurements. Lasing at 2.30 mu m above 330 K under continuous wave operation has been achieved for the laser with four 13 nm quantum wells. By increasing the well width to 19 nm, the continuous wave wavelength has been extended to 2.44 mu m at 290 K, whereas the epitaxial quality and laser performances are deteriorated. For those lasers with well width up to 19 nm, the moderate reduction or the quantum well numbers can restrict the strain accumulation and improve the laser performances. Continuous wave lasing at 2.38 mu m above 300 K has been achieved. (C) 2015 Elsevier B.V. All rights reserved.