(US5336335-A)      A columnar grained polycrystalline sheet is mfd. by: (a) applying granular Si to a setter material having a release coating; (b) reheating; (c) subjecting to a thermal profile which causes melting of the Si from the top downwards, where 25-90% of the depth of the Si is melted and the remaining partially melted Si stabilises the melt and minimises contact with the setter material, and to nucleate subsequent crystal growth; (d) transporting to a growth zone where a thermal profile promotes columnar growth of grain size above 80 microns, perpendicular to the plane of the setter material, and with impurities segregated to the top of the sheet and gettered to the partially melted back surface; (e) annealing with a linear temp. gradient along the setter material to promote low stress cooling; (f) removing the polycrystalline sheet from the setter material, and (g) reusing the setter material.    USE/ADVANTAGE -   Used to make a substrate for a solar cell (claimed). Low cost process. High performance solar cells can be obtd..    (JP6342923-A)      An improved columnar-grained polycrystalline sheet for functioning on a substrate for a solar cell is made by a process comprising: (1) applying granular silicon (200) to a setter material (100) which sulphates the granular silicon, (2) preheating the setter material and granular Si in a preheat zone, (3) subjecting the setter material and granular Si to a thermal ???? (300) which causes melting of the granular Si from the top downwards, wherein 25-90% of the granular Si depth is melted and the partially melted silicon below the melted material functions as a net to stabilise the melt and to minimise molten Si coated with underlying setter and release coating and to nucleate subsequent crystal growth, (4) transporting the melt prod. on the silicon net into a growth zone wherein a thermal profile is created to promote columnar growth from the partially melted Si net upward in a direction approx. perpendicular to the plane of the setter material and where both liq. and a growing polycrystalline layer coexists and impurities are segregated to the top surface of the sheet as well as gathered to the partially melted back surface, (5) transporting the grown sheet into an anneal zone (500) wherein a linear temp. gradient along the direction of setter motion is achieved to promote low stress cooling of the sheet, (6) removal of the polycrystalline sheet from the setter material, facilitated by a release agent (110) (7) reusing the setter material for the making of further columnar-grained polycrystalline sheets.    ADVANTAGE -   Process provides efficient, low cost devices.    (EP591949-B1)      An improved columnar-grained polycrystalline sheet for functioning on a substrate for a solar cell is made by a process comprising: (1) applying granular silicon (200) to a setter material (100) which sulphates the granular silicon, (2) preheating the setter material and granular Si in a preheat zone, (3) subjecting the setter material and granular Si to a thermal ???? (300) which causes melting of the granular Si from the top downwards, wherein 25-90% of the granular Si depth is melted and the partially melted silicon below the melted material functions as a net to stabilise the melt and to minimise molten Si coated with underlying setter and release coating and to nucleate subsequent crystal growth, (4) transporting the melt prod. on the silicon net into a growth zone wherein a thermal profile is created to promote columnar growth from the partially melted Si net upward in a direction approx. perpendicular to the plane of the setter material and where both liq. and a growing polycrystalline layer coexists and impurities are segregated to the top surface of the sheet as well as gathered to the partially melted back surface, (5) transporting the grown sheet into an anneal zone (500) wherein a linear temp. gradient along the direction of setter motion is achieved to promote low stress cooling of the sheet, (6) removal of the polycrystalline sheet from the setter material, facilitated by a release agent (110) (7) reusing the setter material for the making of further columnar-grained polycrystalline sheets.    ADVANTAGE -   Process provides efficient, low cost devices.