CuGaSe2 solar cells prepared by MOVPE

The determination of carrier mobilities in CIGS photovoltaic devices using high-frequency admittance measurements

“…These mobilities do not appear to be correlated in any obvious manner to the cell performance. They all lie well within the range of Hall mobilities determined previously for polycrystalline CIGS samples [1,2], and about an order of magnitude lower than Hall mobilities determined for epitaxial CIGS films [3,4].…”

“…The lower carrier mobility in polycrystalline versus epitaxial CIGS films has been interpreted to imply the existence of potential barriers at grain boundaries that limit carrier transport [4]. However, because the grains are typically 1 Am in size, and comparable to the thickness of our films, we would not expect such grain boundary effects to play a significant role.…”

“…Hole mobilities in both epitaxial and polycrystalline CIGS materials have previously been determined in the traditional manner, using the Hall effect in conjunction with resistivity measurements [1][2][3][4]. Such measurements require insulating substrates with coplanar contacts and thus cannot be performed on working solar cell devices.…”

Ab initiovolume-dependent elastic and lattice dynamical properties of chalcopyriteCuGaSe2

“…CuGaSe 2 -CuInSe 2 structure with high band gap ͑E g ͒ CuGaSe 2 ͑E g = 1.68 eV͒ on top of low gap CuInSe 2 ͑E g = 1.0 eV͒ would form an ideal couple for tandem photovoltaic applications. 2 Structural, electronic, and lattice dynamical properties of both of these materials have been widely studied for the last three decades by a number of experimental and theoretical methods. However, there are still inconsistencies among the reported experimental results especially concerning the lattice dynamical properties which were the subject of recent theoretical work for CuInSe 2 .…”

Carrier Transport Properties

“…This is in accord with the dependence of E 0 on the hole effective mass (i.e., this material parameter also shows no strong dependence on E 0 [6]). The hole mobilities for polycrystalline and single-crystalline Cu(Ga,In)(S,Se) 2 chalcopyrite semiconductors have been measured by the Hall-effect measurements [12][13][14][15]. As for μ e (Figure 7.2), these values are only ideal or limited ones to be expected if high-quality crystals can be actually grown.…”