Influences of SiOx layer thickness on the characteristics of In–Zn–O/SiOx/n-Si hetero-junction structure solar cells

Indium zinc oxide (IZO) film was directly deposited on an n-type Si substrate by pulsed laser deposition (PLD) to form the IZO/SiOx/n-Si hetero-junction solar cell. Analytical results indicated that the thickness and quality of the thermal SiOx layer plays a prominent role in determining the conversion efficiency of the solar cell. The sample containing an about 1.78-nm-thick SiOx layer exhibits an open-circuit voltage of 0.35 V, a short-circuit current density of 28.6 mA/cm2, a fill factor of 34.3%, and an overall conversion efficiency of 3.4% under AM1.5 condition. The effects of the SiOx layer thickness and the associated interface states on the carrier transport are discussed.