Towards the goal of a large-scale quantum computer based on trapped ions,near-field microwaves represent a promising approach to perform the techni-cally challenging key operation of a two-qubit entangling gate. In this thesiswe present the first microwave-driven two-qubit gate in 9Be+ ions employing afirst-order field-independent qubit transition and a scalable surface-electrodeion trap at room temperature. We test the quality of the gate operationby producing a maximally entangled state and measuring the resulting statepreparation fidelity in a reduced tomography procedure. For the best two-qubit gate achieved in the system we find this fidelity to be F = 98.2 ± 1.2 %.Following a comprehensive error analysis based on numerical simulations andexperimentally determined input parameters, we identify current infidelity con-tributions of the apparatus. Here, the natural error source of the microwavenear-field approach, namely fluctuating AC Zeeman shifts, could be reducedto the 10^−4 level due to the optimized design of the employed microwave con-ductor. As we find that the three largest errors can all be reduced upon purelytechnical improvements, higher fidelities are feasible in the future. Besides thegate realization, the thesis also comprises the initial characterization of theemployed ion trap as well as the design and construction of a Raman laserat ∼ 313 nm which is utilized to perform near ground state cooling of radialmodes of a single- and two-ion crystal. Here, ensuing heating rate measure-ments on a single-ion’s radial modes show good agreement with the electric-field noise spectral density expected from literature given the chosen modefrequency and nearest ion-to-electrode distance of 70 µm. Finally, we presentthe operation of a first multi-layer ion trap whose electrode layout features a3-dimensional microwave conductor intended for performing microwave-driventwo-qubit gates. Following a characterization of the resulting near-field pat-tern using a single ion as a local field probe, we find the multi-layer conductorto have significantly better field properties when compared to an equivalentsingle-layer design. Given these promising results, future work will focus onthe integration of similar microwave circuitry in a multi-zone trap array asenvisioned by the QCCD architecture.