We studied Raman spectra of (AlAs)(n)/(GaP)(n) and (AlAs)(n)/(AlP)(n) (n = 1-5) strained short-period superlattices (SLs) grown by gas-source migration-enhanced epitaxy on (0 0 1) GaAs substrates. We found that GaP- and AlAs-like longitudinal optical (LO) phonons in the (AlAs)(n)/(GaP)(n) SLs and AIP-like LO phonons in the (AlAs)(n)/(AlP)(n) SLs were confined in respective layers. We discuss the dependence of observed LO phonon frequency on superlattice period using the linear chain model. © 2005 Elsevier B.V. All rights reserved.