  We present and characterize an atomic vapor cell with silicon ring electrodes
directly embedded between borosilicate glass tubes. The cell is assembled with
an anodic bonding method and is filled with Rb vapor. The ring electrodes can
be externally connectorized for application of electric fields to the inside of
the cell. An atom-based, all-optical, laser-spectroscopic field sensing method
is employed to measure electric fields in the cell. Here, the Stark effect of
electric-field-sensitive rubidium Rydberg atoms is exploited to measure DC
electric fields in the cell of $\sim$5 V/cm, with a relative uncertainty of
10%. Measurement results are compared with DC field calculations, allowing us
to quantify electric-field attenuation due to free surface charges inside the
cell. We further measure the propagation of microwave fields into the cell,
using Autler-Townes splitting of Rydberg levels as a field probe. Results are
obtained for a range of microwave powers and polarization angles relative to
the cell's ring electrodes. We compare the results with microwave-field
calculations. Applications are discussed.
