TECHNOLOGY FOCUS - ELECTRONICS - Preferred Device: The device is fabricated with polymer brushes of only a single species.Preferred Method: The contact between the semiconducting polymer brushes attached to the electrode and at least one other semiconducting material is achieved by either intercalation of the other semiconducting material with the semiconducting polymer brushes; growth of the other semiconducting material as further semiconducting polymer brushes in the gaps between the first semiconducting polymer brushes to give an interpenetrating mixed polymer network; or by the polymerization of a second, different monomer from the end of the semiconducting polymer brushes to give block co-polymer brushes having a bi-layer structure with direct covalent bonds between at least two semiconducting components. The other semiconducting material is a semiconducting polymeric material, nanocrystalline material or a semiconducting small organic molecule. The electrode is coated with a hole-transport layer or an electron-transport layer before the polymer brushes are attached to it. The electrode formed in (i) is coated with a layer of an electronically insulating material.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The small organic molecule is selected from aluminum quinolinol complexes, perylene and its derivatives. The semiconducting nanocrystalline material is selected from semiconducting nanocrystals of cadmium selenide, lead selenide, zinc selenide, cadmium sulfide and zinc sulfide (preferably cadmium selenide nanocrystals).    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: the self-assembled monolayer comprises thiol molecules or siloxane molecules end-capped with an initiator group.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The average length of the polymer brushes is 1 nm - 1 microns (preferably 40 nm). The semiconducting polymer brushes are brushes where the polymer is selected from poly-phenylene-vinylene (PPV), polyfluorene, polynaphthylene, polyindenofluorene, polyphenanthrenyl, poly (acrylate) or its derivative (preferably 9 formulae as given in specification, e.g. group of formula (I), particularly poly(4-diphenylaminobenzyl acrylate), PPV, MEH-PPV, poly(2,7-(9,9-di-n-hexylfluorene)), poly(2,7-(9,9-di-n-octylfluorene)), poly(2,7-(9,9-di-n-octylfluorene)-(1,4-phenylene-((4-sec-butylphenyl)imino)-1,4-phenylene)) (TFB), and poly(2,7-(9,9-di-n-octylfluorene)-3,6-benzothiadiazole) (F8BT)).Z1=O, S, SO, SO2, NR3, N+(R'3)(R3), C(R4)(R5), Si(R'4)(R'5) or P(O)(OR6);R3, R'3 and R3=H, 1-20C (halo)alkyl, 1-20C alkoxy, 1-20C alkoxyalkyl, 1-20C aryl, 6-14C aryloxy, or 6-14C aralkyl (substituted with at least one group of formula N+(R7)3);R7=H, alkyl or aryl;R4, R5, R'4 and R'5=H, 1-20C (halo)alkyl, 1-20C alkoxy, halo, nitro, cyano, 1-20C alkoxyalkyl, 1-20C aryl, 6-14C aryloxy, or 6-14C aralkyl;R4+R5=carbonyl group;R6=H, 1-20C (halo)alkyl, 1-20C alkoxyalkyl, 1-20C aryl, 6-14C aryloxy, or 6-14C aralkyl;e1 and e2=0-3.N.B. R8 and R9 are not defined. EXAMPLE - A field effect transistor was fabricated having a SAM of the initiator above on a silicon dioxide-coated silicone substrate, poly(4-diphenylaminobenzyl acrylate) brushes grown from the SAM initiator and coated with gold.