In quantum mechanics, a wave function $\psi(x, y, z)$ in three dimensions must be normalized such that $\int |\psi|^2 dV = 1$. What are the base SI dimensions of $\psi$ in 3D, and how do they relate to a 1D wave function $\phi(x)$ normalized such that $\int |\phi|^2 dx = 1$?