In this work, the photovoltaic effects, rectification properties and electron tunneling effects of Al Ichlorophyll-a/Hg/In sandwich cells are studied. Some parameters are calculated. The electron effective mass is 0.07 m and the possible position of the lowest conduction band above the Fermi level is 1.4 eV for the aggregated Chl-a film. The barrier height of the junction between Al film and microcrystalline Chl-a is 0.88-0.90eV and the width is 250 Ǻ. The electron diffusion length is 130 Ǻ and absorption constant at 740 nm is 1.1×10^5cm^(-1) in the microcrystalline Chl-a film.