The present invention advantageously provides for, in different embodiments, low-cost deposition techniques to form high-quality, dense, well-adhering Group IBIIIAVIA compound thin films with macro-scale as well as micro-scale compositional uniformities. It also provides methods to monolithically integrate solar cells made on such compound thin films to form modules. In one embodiment, there is provided a method of growing a Group IBIIIAVIA semiconductor layer on a base, and includes the steps of depositing on the base a nucleation and/or a seed layer and electroplating over the nucleation and/or the seed layer a precursor film comprising a Group IB material and at least one Group IIIA material, and reacting the electroplated precursor film with a Group VIA material. Other embodiments are also described.