Planar-type junction

Planar-type junction. An artificial insulating layer and a conducting layer (as a counter electrode) are deposited successively on the sample surface. 

The planar-type junction and point-contact methods were first attempted on the HTSC. The reproducibility, however, was poor, and hence the results obtained by these methods need justification by the other methods. 

If a planar-type junction is ideally fabricated, it should be suited especially for performing measuring with high energy resolution and for measuring temperature dependence, because of the stability of the insulating layer. 

In general, in a planar process, — junctions are formed just below the surface of a siUcon wafer by the implantation of donor ions into a type region or acceptor ions into an n-ty e region. Thus, the general concern is with -p or -n junctions. As the initial wafer concentration of acceptors or donors in sihcon increases from 10 to 10 cm increases from about 0.81 to 1.04 V for a p n junction and is about 10 mV higher for an -p... 

Finally, the working principle of a bulk heteroj unction is summarized schematically in Fig. 5.6. In contrast to a classical bilayer or a planar p-type/n-type junction (analogue to a p-n junction for inorganic semiconductors), the photocarriers in a bulk heterojunction are generated throughout... 

The drawbacks of the mesa structure stated above are acknowledged in US-A-S189297. Instead, a structure having a planar surface is proposed. Isolation junctions are formed by a thermally driven process converting regions in a top layer to an opposite type of material. A method to fabricate the structure without removing it from an epitaxial reactor is also disclosed. 

A schematic diagram of the cross section and dopant distributions in a planar npn bipolar junction transistor in Si are shown in Fig. 9.4a, b. The transistor is made by implanting donors at high concentrations, ND, into the n-type Si to form the emitter, and implanting a lower concentration, NA, of acceptors deeper into the n-type Si to form the p-type base. 

Ghezzo et al [13] reported on ion implanted planar p-n junction 6H-SiC diodes fabricated by ion implantation of B into n-type SiC with the donor concentration of 9x 1015cm 3. The implantation was performed at 25 °C and 1000°C followed by a 1300°C post-implant furnace anneal. The diodes had an ideality factor of 1.77 at room temperature, the reverse leakage current of 1 O 10 A cm 2 at -10 V and the reverse breakdown voltage of -650 V. 

The host metal complex has the three-dimensional structure consisting of the two-dimensionally extended cyanometal complex sheets and of the 1,4-diaminobutane ligands bridging adjacent sheets at the respective Cd atoms in the sheets. The Cd atoms are alternately linked with the square-planar Ni(CN)i moieties at the N-ends at each Cd-N junction the metal complex network bends to give a wavy structure of the sheet similar to those observed for Hofmann-mea-type pyrrole clathrate [14] and Hofmann-dma-type ones [8,9]. 1,4-Diaminobutane takes a trans-cis conformation of its N(3)-C(3)-C(4)-C(5)-C(6)-N(4) skeleton on the mirror plane at y=l/4 except the C(5) which is distributed statistically at both sides of the mirror plane the positions of hydrogen atoms attached to C(4) and C(6) atoms have been calculated in relation to both the... 

The planar 100 surfaces are type I and so have a neutral layer structure as expected, these are found to be the most stable surfaces in the calculations. The 110 surfaces are type III and give rise to considerably higher surface energies. In this case, the removal of alternate rows of Mg and 0 lead to a ridge structure formed from the junction of two of the 100 family of planes. As the height of... 

Alternatively the PN junction can be made by growing the whole crystal with a moderate amount of acceptor material already mixed into it, and then diffusing a relatively larger amount of donor atoms into half of it, overwhelming the effect of the acceptors in that half. Again, where the two types meet there is a planar junction. 

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