Experiments in view of developing a four-junction cells using metallic wafer bonding have been conducted [11]. The most difficult point is the interconnection between the cells. It must meet three requirements: it must be optically transparent to allow non-absorbed light to be transmitted from one cell to the one under; it must be electrically conductive; […]

Transistors made on III-V films transferred onto silicon have been realized [20]. Lattice-matched InAlAs/InGaAs layers were grown in the reverse order compared to conventional HEMT structures on a 2 in InP substrate with etch stop layers between the substrate and the InAlAs/InGaAs. The InP wafer with the grown layers was bonded onto a 2 in […]

The techniques of film transfer have already been used for transistors and solar cells applications. We give here some examples of structures and devices realized using bonding and transfer. (b)

The transfer of thin films with patterned structures onto different substrates is very attractive for applications such as thin-film transistors on glass or quartz for TFT- LCDs, intelligent sensors and actuators or smart power. For example, metal lines embedded in an oxide have been transferred onto a Si substrate [15]. In this example (see figure […]

C Jaussaud1, E Jalaguier2 and D Mencaraglia3 1 CEA/DTEN 2 CEA /DTS 3 Supelec/LGEP 12.1 Introduction Wafer-bonding and film transfer have been developed in the microelectronic industry and these techniques are presently used to make silicon-on-insulator (SOI) structures. They are also of interest for photovoltaic cells and many studies have been done to develop thin-film […]

Lattice-matched In0.53Ga0.47As/InP heterostructures were developed initially for fabricating infrared photodetectors. Then, these diodes were used as laser power converters [64] and as bottom cells for monolithic InP(top)/InGaAs(bottom) [62] or mechanically stacked GaAs (top)/InGaAs(bottom) [31,32] tandems. InGaAs layers were grown on InP substrates by LPE [31,32,63] and by MOCVD [62] methods. A 6% efficiency (AM0, 100 […]

Epitaxial InAsSbP/InAs heterostructures for TPV cells have been grown [55,71­73] by the LPE method. Narrow-gap epitaxial InAsSbP (0.45-0.48 eV) cells were fabricated [73] from p-InAsSbP/n-InAsSbP/n-InAs heterostructures grown on (100) n-InAs substrates. Epitaxial growth of n-InAsSbP quaternary layers Figure 11.16. Cross section of a TPV cell based on the p-InAsSb/n-InAsSbP/n-InAs heterostructure. lattice-matched to InAs was carried […]

The heterostructure of the monolithic tandem TPV cell (figure 11.15) consists of an n-GaSb (substrate); an n-p InxGai-xAsySbi-y (EG = 0.56 eV, 1-3 ^m thick n-layer and 0.2-0.5 ^m thick p-layer) bottom cell; a p++-n++GaSb (0.8 ^m total thickness) tunnel junction; an np GaSb (n-layer 3-5 ^m thick and a p-layer 0.2-0.5 ^m thick) top […]