TECHNOLOGY FOCUS - IMAGING AND COMMUNICATION - Preferred Process: The process further comprises: depositing an ink containing In(S(s)Bu)3 after step (e); exposing the main layer to chalcogen vapor; and applying heat, light or radiation or adding one or more chemical or crosslinking reagents to the second or first ink before depositing the second or first ink onto the substrate. The combined thickness of the initial and main layers after heating is 1-3 microns. The depositing is carried out by spraying, spray coating, spray deposition, spray pyrolysis, printing, screen printing, inkjet printing, aerosol jet printing, ink printing, jet printing, stamp printing, transfer printing, pad printing, flexographic printing, gravure printing, contact printing, reverse printing, thermal printing, lithography, electrophotographic printing, electrodepositing, electroplating, electroless plating, bath deposition, coating, wet coating, dip coating spin coating, knife coating, roller coating, rod coating, slot die coating, meyerbar coating, lip direct coating, capillary coating, liquid deposition, solution deposition, layer-by-layer deposition, spin casting and/or solution casting. The substrate coated with an electrical contact layer is a conducting substrate.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The first or second ink contains metal compound of formula (M(alk)M(B1)(ER)4), (M(alk)(ER)), NaIn(Se(n)Bu)4, NaIn(Se(t)Bu)4, NaIn(Se(n)Bu)4, NaIn(Se(n)Pr)4, NaIn(Se(n)hexyl)4, NaGa(Se(n)Bu)4, NaGa(Se(s)Bu)4, NaGa(Se(t)Bu)4, NaGa(Se(n)Pr)4, NaGa(Se(n)hexyl)4, Na(Se(n)Bu), Na(Se(s)Bu), Na(Se(t)Bu), Na(Se(n)Pr), Na(Se(n)hexyl), Na(Se(n)Bu), Na(Se(s)Bu), Na(Se(t)Bu), Na(Se(n)Pr) or Na(Se(n)hexyl), where s, n and t are not defined. The substrate is a semiconductor, a doped semiconductor, silicon, gallium arsenide, insulators, glass, molybdenum glass, silicon dioxide, titanium dioxide, zinc oxide, silicon nitride, a metal, a metal foil, molybdenum, aluminum, beryllium, cadmium, cerium, chromium, cobalt, copper, gallium, gold, lead, manganese, molybdenum, nickel, palladium, platinum, rhenium, rhodium, silver, stainless steel, steel, iron, strontium, tin, titanium, tungsten, zinc, zirconium, a metal alloy, a metal silicide, a metal carbide, a polymer, a plastic, a conductive polymer, a copolymer, a polymer blend, a polyethylene terephthalate, a polycarbonate, a polyester, a polyester film, a mylar, a polyvinyl fluoride, polyvinylidene fluoride, a polyethylene, a polyetherimide, a polyethersulfone, a polyetherketone, a polyimide, a polyvinylchloride, an acrylonitrile butadiene styrene polymer, a silicone, an epoxy, paper and/or coated paper.M(alk) = Li, Na or K;M(B1) = In, Ga or Al;E = S or Se; andR = alkyl or aryl.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The second polymeric precursor compound is a copper indium selenide or copper indium gallium diselenide precursor. The second polymeric precursor compound is a copper aluminum indium gallium selenide (CAIGS) precursor containing silver atoms or CAIGAS precursor containing aluminum atoms. The initial layer is made from one or more individual layers of the first ink. The main layer is made from one or more individual layers of the second ink. The inks contain a polymeric precursor compound dissolved in an organic solvent. Each heating process is a process comprising converting the layer at 100-400 degrees C (preferably 170-350 degrees C), and annealing the layer at 450-650 degrees C (preferably 450-575 degrees C). The first ink or second ink contains 0.01-2 atom percent sodium ions.