Disclosed are methods for preserving the integrity of large-sized growth substrates. The methods pertain to accelerating the rate of epitaxial liftoff, and improved cleaning and etching steps. Also disclosed are devices produced therein.

The present disclosure enables high-volume cost effective production of three-dimensional thin film solar cell (3-D TFSC) substrates. Pyramid-like unit cell structures 16 and 50 enable epitaxial growth through an open pyramidal structure 3-D TFSC embodiments 70, 82, 100, and 110 may be combined as necessary. A basic 3-D TFSC having a substrate, emitter, oxidation on the emitter, and front and back metal contacts allows for simple processing. Other embodiments disclose a selective emitter, selective backside metal contacts, and front-side SiN ARC layers. Several processing methods, including process flows 150, 200, 250, 300, and 350, enable production of these 3-D TFSCs.

A device, system, and method for solar cell construction and bonding/layer transfer are disclosed herein. An exemplary structure of solar cell construction involves providing a monocrystalline donor layer. A solder bonding layer bonds the donor layer to a carrier substrate. A porous layer may be used to separate the donor layer.

A handle substrate having at least one metallization region is provided on a stressor layer that is located above a base substrate such that the at least one metallization region is in contact with a surface of the stressor layer. An upper portion of the base substrate is spalled, i.e., removed, to provide a structure comprising, from bottom to top, a spalled material portion of the base substrate, the stressor layer and the handle substrate containing the at least one metallization region in contact with the surface of the stressor layer.

There is disclosed a method of preserving the integrity of a growth substrate in a epitaxial lift-off method, the method comprising providing a structure comprising a growth substrate, one or more protective layers, a sacrificial layer, and at least one epilayer, wherein the sacrificial layer and the one or more protective layers are positioned between the growth substrate and the at least one epilayer; releasing the at least one epilayer by etching the sacrificial layer with an etchant; and heat treating the growth substrate and/or at least one of the protective layers.

Various laser processing schemes are disclosed for producing various types of hetero-junction and homo-junction solar cells. The methods include base and emitter contact opening, selective doping, metal ablation, annealing to improve passivation, and selective emitter doping via laser heating of aluminum. Also, laser processing schemes are disclosed that are suitable for selective amorphous silicon ablation and selective doping for hetero-junction solar cells. Laser ablation techniques are disclosed that leave the underlying silicon substantially undamaged. These laser processing techniques may be applied to semiconductor substrates, including crystalline silicon substrates, and further including crystalline silicon substrates which are manufactured either through wire saw wafering methods or via epitaxial deposition processes, or other cleavage techniques such as ion implantation and heating, that are either planar or textured/three-dimensional. These techniques are highly suited to thin crystalline semiconductor, including thin crystalline silicon films.

One embodiment of the present invention provides a double-sided heterojunction solar cell module. The solar cell includes a frontside glass cover, a backside glass cover situated below the frontside glass cover, and a number of solar cells situated between the frontside glass cover and the backside glass cover. Each solar cell includes a semiconductor multilayer structure situated below the frontside glass cover, including: a frontside electrode grid, a first layer of heavily doped amorphous Si (a-Si) situated below the frontside electrode, a layer of lightly doped crystalline-Si (c-Si) situated below the first layer of heavily doped a-Si, and a layer of heavily doped c-Si situated below the lightly doped c-Si layer. The solar cell also includes a second layer of heavily doped a-Si situated below the multilayer structure; and a backside electrode situated below the second layer of heavily doped a-Si.

A bonded semiconductor light-receiving device including an epitaxial layer to serve as a device-functional layer, and a support substrate made of a material different from that of the device-functional layer and bonded to the epitaxial layer via a bonding material layer. The device-functional layer has a bonding surface with an uneven pattern formed thereon.

The present inventive concept relates to a solar cell manufacturing method, a solar cell manufactured thereby, and a substrate for a solar cell. The solar cell manufacturing method involves forming a separating portion for separating a substrate, which is for manufacturing the solar cell, into a plurality of pieces. The solar cell manufacturing method comprises: a step for preparing the substrate; a first substrate etching step for forming a first groove in one surface of the substrate; a second substrate etching step for forming a second groove inside the first groove; and a third substrate etching step for etching the substrate including the second groove, wherein the separating portion includes the first groove and the second groove.

A space power module (SPM) can include a plurality of solar cells, a plurality of interconnect elements, and a plurality of planar pieces of cover glass forming a mosaic sheet of cover glass overlaying light receiving surfaces of the plurality of solar cells. Each interconnect element can connect two adjacent solar cells of the plurality of solar cells and can be arranged in-plane relative to the two adjacent cells. The plurality of planar pieces of cover glass can cover at least portions of the plurality of interconnect elements.