| Solar glass | Rigid support and protective front sheet; commonly about 2–4 mm in modules. Thin glass is also used as a substrate in some thin-film designs. | 0.8–1.2 W/m·K | About 3–9 × 10−6/K, depending on glass composition | Transparent, weather-resistant, electrically insulating, and widely used in durable module construction. | Heavy and brittle; ordinary glass is not suitable when a flexible carrier is required. | Conventional rigid modules and glass-based thin-film cells. |
| Crystalline silicon wafer | The semiconductor wafer is both the active cell material and its structural support; common cell wafers are roughly 100–200 μm thick. | About 130–150 W/m·K near room temperature; varies with temperature and wafer properties | About 2.6 × 10−6/K | High thermal conductivity and a well-established role in high-efficiency crystalline-silicon cells. | Brittle and generally unsuitable for bending; it is an active semiconductor, not a separate passive carrier. | Wafer-based monocrystalline and multicrystalline silicon cells. |
| Stainless-steel foil | Flexible conductive substrate for thin-film devices; commonly tens to a few hundred micrometres thick. | About 14–16 W/m·K | About 16–18 × 10−6/K | Mechanically robust, bendable in thin gauges, and compatible with roll-to-roll handling in suitable processes. | Opaque and electrically conductive, so an insulating or barrier layer may be needed; metal expansion can stress deposited films. | Flexible thin-film cells where a durable, opaque metal support is acceptable. |
| Polyimide film | Lightweight flexible substrate; film thickness is often about 25–125 μm, depending on the application. | About 0.12–0.3 W/m·K | Typically about 20–60 × 10−6/K, depending on formulation and direction | Lightweight, electrically insulating, and flexible; some grades tolerate elevated processing temperatures. | Low heat conduction and relatively high thermal expansion; temperature, moisture, and barrier requirements depend on the specific grade. | Lightweight flexible photovoltaics using processes compatible with the selected film. |
| Alumina ceramic | Rigid insulating support for specialized or laboratory devices; thickness varies with design and handling needs. | About 20–30 W/m·K | About 6–8 × 10−6/K | Electrically insulating, dimensionally stable, and more thermally conductive than ordinary glass. | Rigid, brittle, and generally heavier or more costly than polymer films; opaque grades cannot serve as a transparent front carrier. | Specialized cells that need an insulating, heat-tolerant rigid substrate. |
| Flexible glass | Thin glass substrate or cover; commonly tens to a few hundred micrometres thick, depending on product design. | Approximately 0.8–1.2 W/m·K | Depends on composition; often similar to other photovoltaic glasses | Can combine transparency and a glass surface with limited bendability at sufficiently small thickness. | Still vulnerable to fracture and edge damage; allowable bend radius and handling limits are product-specific. | Lightweight or curved designs that need glass-like surface and barrier properties. |
| How to choose: There is no single best carrier for every solar cell. The right choice depends on cell architecture, processing temperature, optical requirements, flexibility, electrical isolation, durability, weight, and cost. Property values are approximate typical ranges; actual values vary with composition, grade, thickness, and temperature. |