  The Dirac field, spin 1/2 particles, is investigated in phase space. The
Dirac propagator is defined. The Thermo Field Dynamics (TFD) formalism is used
to introduce finite temperature. The energy-momentum tensor is calculated at
finite temperature. The Stefan-Boltzmann law is established and the Casimir
effect is calculated for the Dirac field in phase space at zero and finite
temperature. A comparative analysis with these results in standard quantum
mechanics space is realized.
