Introduction of Thin Film Solar Cells

The integrated system for the solar cells can be developed in a smaller region for instead of the large area with the economic structures. The process can be carried out by depositing the electrolyte layer on the subsequent area. Thin film processing for the solar cells is based on different methodologies in physical vapor deposition, chemical vapor deposition, pulse laser deposition and the sol-gel method. The deposition of the photosensitive layer in the present work is by the electrode layer. The technique used in the process permits connection between three layers and these layers are insulated solar cells (Thalheimer & Messerschmitt-Bölkow-Blohm, 1988).      

Method of Thin Film Solar Cells

The integrated system includes connections of layers in series for the three layers. The formation of the layer is itself a complex process, the first layer is the electrolyte layer, then a photo emissive layer and the third layer is the electrode layer. The photo emissive layer is the composition of sublayers. The methodology used in the process is DE-OS No 28 39 038 and the intended outcome is the development of a series of connection layers (Thalheimer & Messerschmitt-Bölkow-Blohm, 1988). The first layer is a barrier layer that is composed of tin oxide and the glass substrate is used for the formation of layer (Thalheimer & Messerschmitt-Bölkow-Blohm, 1988). The second layer is composed of cadmium sulfide and cuprous sulfide (Copper Sulphide I). The process consists of two steps including

1. Separation of each individual solar cell.

2. Preparation of photo emissive layer in the first electrode layer.

3. The first step is done by punching and miter cutting, on the other hand, the second step is done by electro erosion, etching, laser irradiation, and masking.

The photo emissive layer is produced by removing the layer from the center to generate a gap in the photo sensitive layer. The margin is displaced in the removing method. After the generation of the gap two insulating masses were applied to the narrow layer gaps produced on the electrolyte material (Lee & Ebong, 2015). The insulating masses were exposed to the surface by using the adhesive material. The second layer is produced by chemical vapor deposition on the surface of the material used for the formation of the thin film. The ultrasonic energy was applied on the surface of the material. Due to the application of ultrasonic energy, the copper layer was eroded and produced structures on the surface of the material. All the electrode layers were then electrically connected with each other in a series combination (Thalheimer & Messerschmitt-Bölkow-Blohm, 1988).

The connections were developed on the upper sides of these layers. Even the production method was expensive but on the industrial level, the production of solar cells can be increased by thin film development on the electrodes of cells. The application of the second layer by the vapor deposition process and separation process was interrupted by adhesive element and insulating masses on both sides. The insulating material becomes superfluous for the second layer and structures produced on the surface of the electrolyte (Lee & Ebong, 2015).        

How it works the Thin Film Solar Cells

The thin layer produced on the surface behaves distinctly for the series of connections. In case of photosensitive layer, there are 4 sub layers produced of silicon, the initial three layers of the electrode are transparent and are made of indium tin oxide. There are different possibilities for the production of layers with different materials (Thalheimer & Messerschmitt-Bölkow-Blohm, 1988). The possible layers of material are mentioned below,

(Thalheimer & Messerschmitt-Bölkow-Blohm, 1988)

The covered gap in the first and second layer is necessary for the application of insulating metals on the edges. In the mentioned process three layers are deposited on the surface and each layer has its own properties based on the nature of the material used in the process. The electrode layer in the solar cell is a conductive material and comprises of the etching process. The individual properties of the materials used for the formation of a thin layer on the cell have a significant impact on the electrical and other properties of the material used in the formation of the solar cell (Lee & Ebong, 2015).

Figure 1: Thin layer formation (Thalheimer & Messerschmitt-Bölkow-Blohm, 1988)

Individuality of Thin Film Solar Cells

The advantage of using thin film process was for improvement of solar cells. The individuality of processing is the overall performance of the cells. The separation of the photosensitive layer is for large area deposition and layer structuring. The advantage of using thin film methodology can be inferred for higher and relatively subsequent disclosure. The properties of the electrode changes due to the addition of thin film on the surface and electrode layer individuality are larger area deposition process at the commercial level (Thalheimer & Messerschmitt-Bölkow-Blohm, 1988). In fact, the process for the formation of all the layers is different and innovative that can be applied to any kind of layer formation process and at any scale. The deposition of the thin film can be done by many processes and pulse laser ablation is the most efficient way for the formation of a thin layer on the surface of the substrate. The laser ablation is a process of removing the material from the surface of material and plasma formed during the process decays and then produces a thin layer of atoms on the surface of the substrate (Lee & Ebong, 2015).        

Architecture of Thin Film Solar Cells

            Thin layer process is getting more attraction due to efficient outcomes of the process as well as economic processing of material. The layer produced on the surface induces variation in the structural morphology of material, thermal properties of the material, and electrical properties of the material. The deposition of the layer can be an ambient environment of gasses and in the vacuum. In the vacuum process, the material is removed from the target surface and then deposited on the substrate. The initially removed particles are deposited on the surface. The addition of a thin layer on the surface improves the lifetime of solar cells and works as resistant to corrosion. The insulating mass on the edges of the electrolyte layer and gap produces structures on the surface (Lee & Ebong, 2015).

Figure 2: insulating metal added to edges (Thalheimer & Messerschmitt-Bölkow-Blohm, 1988)

Conclusion on Thin Film Solar Cells

            The integrated cells and system for the solar cells can be generated by application of a thin film solar cell method on the surface of the substrate. In this process, the layer is deposited on the surface that increases material properties. The deposited layer sequences are composed of substrate and layer sequence for the first and second electrode. The deposition of the surface layer and electrode layer can be applied to different areas such as on larger area and nanometer area. The area of the electrode is always determined earlier than the processing. The margin for the exposed area is also predetermined that is applicable to the insulating material and marginal area.

References of Thin Film Solar Cells

Lee, T. D., & Ebong, A. (2015). Thin film solar technologies: a review. 2015 12th International Confe, 2(397), 1-10.

Thalheimer, K., & Messerschmitt-Bölkow-Blohm. (1988). PROCEDURE FOR PRODUCING AN INTEGRATED SYSTEM OF THIN FILM SOLAR CELLS CONNECTED IN SERIES. United States Patent, 01(01), 1-4.