Abstract: The target comprises a transparent substrate, an N-type transparent conductive film formed on the substrate, a P-type photoconductive film formed on the N-type conductive film and a heterojunction formed at the interface between the N- and P-type films. The P-type photoconductive film contains selenium, tellurium and arsenic of which selenium and arsenic are distributed continuously from the heterojunction throughout the thickness of the P-type photoconductive film whereas the distribution of tellurium is spaced from the heterojunction and localized in the vicinity of the heterojunction. The total amount of arsenic contained in the P-type photoconductive film ranges from 2.5 to 6% by weight.

Abstract: The target comprises a transparent substrate, an N-type transparent conductive film formed on the substrate, a P-type photoconductive film formed on the N-type conductive film and a heterojunction formed at the interface between the N- and P-type films. The P-type photoconductive film contains selenium, tellurium and arsenic of which selenium and arsenic are distributed continuously from the heterojunction throughout the thickness of the P-type photoconductive film whereas the distribution of tellurium is spaced from the heterojunction and localized in the vicinity of the heterojunction. The total amount of arsenic contained in the P-type photoconductive film ranges from 2.5 to 6% by weight.

Abstract: A photoconductive film comprises a first region containing Se in which Te and an element capable of forming deep levels in Se are added at concentrations lower than 10 atomic % inclusive on average, respectively, a second region disposed on the first region and containing Se in which Te is added with a continuous distribution of concentration having a peak value greater than 15 atomic % inclusive, a third region disposed on the second region and containing Se in which an element capable of forming deep levels in Se is added with a continuous distribution of concentration having a peak value greater than 15 atomic % inclusive, and a fourth region disposed on the third region and containing Se in which Te and an element capable of forming deep levels in Se are added at concentrations lower than 10 atomic % inclusive on average, respectively.

Abstract: In a target structure for use in a photoconductive image pickup tube, a P-type photoconductive film is deposited on an N-type transparent conductive film which is deposited on a transparent substrate. The P-type photosensitive film comprises first and second photoconductive substances. The commencement of the deposition of the first photoconductive substance is delayed a predetermined time from that of the second photoconductive substance thereby forming a film of the first photoconductive substance which is not contiguous to the junction surface between the N-type transparent conductive film and the P-type photoconductive film.

Abstract: In a method of manufacturing a target structure for use in a photoconductive image pickup tube when depositing a P-type photoconductive film on an N-type transparent conductive film deposited on one side of a transparent substrate which acts as an incident window of the image pickup tube, the P-type photoconductive film is made up of first and second photoconductive substances. The commencement of the deposition of the first photoconductive substance is delayed a predetermined time than that of the second photoconductive substance and the deposition of the first photoconductive substance is terminated before completion of the deposition of the second photoconductive material thereby forming a layer of the first photoconductive substance not contiguous to the junction between the N-type transparent conductive film and the P-type photoconductive film and having a predetermined thickness.

Abstract: An image pickup tube target wherein a rectifying contact which is formed at a boundary of a first layer of a material selected from the group consisting of tin oxide, indium oxide, titanium oxide, cadmium sulfide, zinc sulfide, cadmium selenide, zinc selenide, n-type germanium, n-type silicon and mixture thereof, and a second layer of a material mainly consisting of selenium and including halogen, is reversely biased and operated at a region where signal current is saturated with respect to applied voltage. The second layer of the material includes 50 atomic percent or more of selenium and 0.1 - 1000 atomic ppm of halogen. More preferably, the second layer comprises 3-20 atomic % of arsenic, 0.1-20 atomic ppm of iodine and balance mainly consisting of selenium.