Rapid heating with an electron beam has been used to react overlayers of rare‐earth (RE) metals with (111) Si, forming epitaxial layers of silicides of Y, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. Under conventional furnace annealing, forming such silicides on Si typically leads to rough, pitted surfaces. The use of fast beam heating not only results in a much smoother surface topology but also helps promote epitaxial growth on (111) Si in both solid and liquid phase reactions. These epitaxial silicides have a hexagonal RESi∼1.7 structure (defected AlB2 type). Their orientation with the Si substrate is (0001)∥(111), with predicted lattice mismatches ranging from +0.83 to −2.55%.