ZnO is a novel wide band gap semiconductor material for optoelectronic applications and has received extensively attention in recent years. The growth of high quality ZnO materials and p-type doping for ZnO films are key techniques for the development of ZnO based optoelectronic devices. Our previous study shows that ZnO films grown by ultrasonic spray pyrolysis (USP) can easily be doped to p-type

and the resulting p-type film exhibits low resistivity and high hole concentration. However

USP method is difficult to grow ZnO films with high quality crystal structure

which limits the application of ZnO films by USP. In this paper

we aim to improve the crystallinity of the USP-grown ZnO films by introducing a high quality ZnO seeding layer. We firstly deposited a ZnO seeding layer on Si(100) by pulsed laser deposition (PLD)

and then grew ZnO film on the seeding layer by USP method. The ZnO seeding layer by PLD shows high quality crystal structure with highly (002) orientation and atomic scale smooth surface. The effect of ZnO seeding layer on the crystal quality and photoelectrical properties has been studied. Results indicate that by the induction of the seeding layer

ZnO film changes from multi-oriented polycrystalline structure to highly (002) oriented structure with significantly enhanced crystallinity. The resultant film possesses columnar microstructure perpendicular to the substrate and exhibits smooth

dense and uniform morphology. In order to characterize the photoelectric properties of ZnO films

we measured the photoelectric response of ZnO/Si heterojunction. It is concluded that ZnO/Si heterojunction formed by ZnO film with seeding layer exhibits markedly higher photocurrent at reverse bias and significant pen-circuit photovoltage at UVillumination

compared with the heterojunction by ZnO film without seeding layer. The present study provides a good starting point for preparation of p-type ZnO films with both excellent electrical properties and high quality crystal structure.