New thin‐film dielectrics and nanolaminates have been synthesized via aqueous‐solution deposition of Hf and Zr sulfates, where facile gelation and vitrification of the precursor solution have been achieved without organic additives. X‐ray reflectivity, imaging, and metal‐insulator‐metal capacitor performance reveal that smooth, atomically dense films are readily produced by spin coating and modest thermal treatment (T < 325 °C). Dielectric characteristics include permittivities covering the range of 9–12 with breakdown fields up to 6 MV cm–1. Performance as gate dielectrics is demonstrated in field‐effect transistors exhibiting small gate‐leakage currents and qualitatively ideal device performance. The low‐temperature processing, uniformity, and pore‐free nature of the films have also allowed construction of unique, high‐resolution nanolaminates exhibiting individual layers as thin as 3 nm.