A standard RF-PECVD reactor is used to grow epitaxial SiGe layers at 175° C on c-Si (100) substrates. By adding GeH 4 to SiH 4/H 2 plasmas, we show for the first time epitaxial SiGe alloys with Ge atomic fraction up to 35% grown at such low temperature. Few μm thick layers are used as an absorber in the wafer equivalent approach: thin film c-Si (p++)/epi-Si 1-x Ge x/a-Si: H (n+) heterojunction solar cells are fabricated. Structural and electronic properties of these materials are investigated using Ellipsometry, Raman, TEM, J (V) characteristics and EQE. Simulations of device structure are performed with PC1D. Stress induced lift off enables detachment and transfer of ultra-thin Si layers of 1 cm 2, on inexpensive substrate. Crystal quality is not affected by the transfer process, and first proof of concept of PECVD epitaxial ultrathin transferred solar diode is obtained.