Micro cavities (MCs) with a small effective volume (Veff ) and a high quality factor (Q) are promising for applications in nonlinear optics, sensing, low-threshold lasers, single photon sources, quantum information processing and cavity quantum electrodynamics (CQED) for individual quantum dots (QDs) in the low temperature emission spectra. Near-field mapping of the emission spectra from embedded self-assembled QD provides a better means to understand and control those applications. This thesis is largely focused on the development of a variety of optically- pumped micro-cavities, including photonic crystals (PCs), microdisks (MDs), and microrings (MRs), utilizing an asymmetric waveguide structure of InAs/AlGaAs or InP/GaInP with ultra-small Veff and high-Q. Good isolation of the waveguide layer from substrate by using a wafer bonding technique with a spin-on-glass or wet oxidation of AlGaAs to produce a stable structure for subsequent device development has been achieved. Both far-field and near-field luminescence have been carried out as a function of temperature, along with near-field imaging and finite-difference-time- domain (FDTD) calculations to study the PC defect and Whispering Gallery Modes (WGMs) inside of the MCs. Optically-pumped lasing of microdisk structures has been investigated in both semiconductor systems. Ultra-low lasing thresholds for InP MD and MR lasers at both room temperature and low temperature are demonstrated for the first time.