NOVELTY - Preparing solar cell module (20) involves subjecting pre-lamination assembly to vacuum force of 1-100 torr in closed chamber, where one side of assembly is exposed to first heat source and assembly comprises solar cell layer (14) having electrically interconnected solar cell and encapsulant sheet layer; increasing temperature of heat source to 50-150 degrees C; releasing vacuum force within chamber and exposing assembly to ambient pressure; exposing side of assembly to second heat source; and applying pressure of 5-120 psi to assembly by passing it through pair of confronting pressing members.    USE - For preparing a solar cell module, where the solar cells are wafer-based solar cells selected from crystalline silicon and multi-crystalline silicone based solar cells; or are thin film solar cells selected from amorphous silicon, microcrystalline silicon, cadmium telluride, copper indium selenide, copper indium/gallium diselenide, light absorbing dyes, and organic semiconductor based solar cells (claimed) used as energy source.    ADVANTAGE - The method is improved non-autoclave process for manufacturing solar cell modules having sufficient adhesion strength between the component layers.    DETAILED DESCRIPTION - Preparing a solar cell module (20) involves subjecting a pre-lamination assembly to a vacuum force of 1-100 torr within a closed chamber, where one side of the assembly is exposed to a first heat source, the pre-lamination assembly is optionally heated to greater than or equal to 25 degrees C and the pre-lamination assembly is maintained at such vacuum and optional temperature condition for 1-15 minutes, where the pre-lamination assembly comprises a solar cell layer (14) comprising at least one electrically interconnected solar cell, where the pre-lamination assembly has a front sun-facing side and a back non-sun-facing side and at least one encapsulant sheet layer that is positioned to one side of the solar cell layer; increasing the temperature of the first heat source to heat the pre-lamination assembly to 50-150 degrees C while applying a pressure of 1 atm to a surface of the pre-lamination assembly within the closed chamber, and maintaining the pre-lamination assembly at the vacuum, temperature and pressure conditions for a period of time to achieve edge seal of the pre-lamination assembly; releasing the vacuum force within the chamber and exposing the pre-lamination assembly to ambient pressure; further exposing at least one side of the pre-lamination assembly to a second heat source which heats the pre-lamination assembly to a temperature of 70-150 degrees C for about 1-30 minutes; and applying a pressure of 5-120 psi (about 0.035-0.827 MPa) to the pre-lamination assembly by passing it through at least one pair of confronting pressing members to form the solar cell module. The first three steps are conducted within a vacuum laminator chamber with the first heat source being a heated platen positioned at one side of the vacuum laminator, where the second heat source used in further exposing step is selected from forced air ovens, convection ovens, radiant heat sources, infrared light, microwave ovens and/or hot air. The pre-lamination assembly further comprises an incident layer being an outermost surface layer of the assembly and positioned on the sun-facing side of the solar cell layer, where the incident layer is selected from glass sheets, polymeric sheets comprising a polymer selected from polycarbonates, acrylics, polyacrylates, cyclic polyolefins, polystyrenes, polyamides, polyesters and/or fluoropolymers, and polymeric films comprising a polymer selected from polyesters, polycarbonates, polyolefins, norbornene polymers, polystyrene, styrene-acrylate copolymers, acrylonitrile-styrene copolymers, polysulfones, nylons, polyurethanes, acrylics, cellulose acetates, cellophane, polyvinyl chlorides), and/or fluoropolymers. The pre-lamination assembly further comprises a backing layer being an outermost surface layer of the assembly and positioned on the non-light receiving side of the solar cell layer, where the backing layer is selected from glass sheets, polymeric sheets comprising a polymer selected from polycarbonates, acrylics, polyacrylates, cyclic polyolefins, polystyrenes, polyamides, polyesters and/or polymers and polymeric films comprising a polymer selected from polyesters, polycarbonates, polyolefins, norbornene polymers, polystyrene, styrene-acrylate copolymers, acrylonitrile-styrene copolymers, polysulfones, nylons, polyurethanes, acrylics, cellulose acetates, cellophane, polyvinyl chlorides) and/or fluoropolymers. The pre-lamination assembly consists of in order of position: a glass incident layer (10), a front encapsulant layer (12) positioned to the sun-facing side of the solar cell layer, the solar cell layer, a back encapsulant layer (16) positioned to the non-light receiving side of the solar cell layer, and a glass backing layer (18), where one or both of the front and back encapsulant layers comprises a thermoplastic polymer selected from acid copolymers, and/or ionomers of acid copolymers.    DESCRIPTION OF DRAWING(S) - The figure shows cross-sectional view of a wafer-based solar cell module prepared by the process.    Incident layer (10)    Front encapsulant layer (12)    Solar cell layer (14)    Back encapsulant layer (16)    Backing layer (18)    Solar cell module (20)