Quantum bits (qubits) are regarded as the building blocks of a quantum computer, which have significant implications in quantum information science. The superconducting qubit is a solid platform for quantum computing, where the Transmon qubit based on the Josephson junction or the SQUID structure is widely designed and researched. Microwave design and electromagnetic simulation of a superconducting qubit is a crucial way to determine and enhance the qubit performance in reality. The geometry of a superconducting qubit structure should be optimized to achieve the desired equivalent capacitance and consequently the resonant frequency through the external magnetic flux adjustment. In this thesis, a special superconducting qubit for lower energy loss named 'Pokemon' qubit is analyzed, with the role of different capacitance geometry in the qubit studied. This thesis also presented a comparative analysis between the in-plane capacitive structure and the flip-chip capacitance. The results pave the way for future modular quantum processing units utilizing flip-chip technology.