The present invention provides high density, non-volatile memory devices incorporating winged trimers of porphyrinic macrocycles. In preferred embodiments, the two wing porphyrinic macrocycles are the same, and both are different from the center macrocycle. Such molecules are relatively easy to synthesize, have four different and distinguishable oxidation states, and thus provide molecules, information storage media and apparatus that store two bits of information.
A memory system includes storage cells, a respective one of which is configured to store a fixed charge therein when a write voltage applied thereto is above a predetermined threshold voltage and to discharge the fixed charge therefrom when the write voltage applied thereto is below the threshold voltage. The storage cells may be charged and/or discharged at a latency that is a function of a voltage differential between the write voltage and the threshold voltage. A variable-latency write circuit for the storage cells is configured to dynamically vary the voltage differential between the write voltage and the threshold voltage to provide a variable-latency write operation that stores the fixed charge therein or discharges the fixed charge therefrom. Related methods are also discussed.
A light harvesting array useful for the manufacture of devices such as solar cells comprises: (a) a first substrate comprising a first electrode; and (b) a layer of light harvesting rods electrically coupled to the first electrode, each of the light harvesting rods comprising a polymer of Formula I: wherein m is at least 1, and may be from two, three or four to 20 or more; X.sup.1 is a charge separation group (and preferably a porphyrinic macrocycle, which may be one ligand of a double-decker sandwich compound) having an excited-state of energy equal to or lower than that of X.sup.2, and X.sup.2 through X.sup.m+1 are chromophores (and again are preferably porphyrinic macrocycles).
The present invention provides a convergent method for the synthesis of light harvesting rods. The rods are oligomers of the formula A.sup.1 (A.sup.b+1).sub.b, wherein b is at least 1, A.sup.1 through A.sup.b+1 are covalently coupled rod segments, and each rod segment A.sup.1 through A.sup.1+b comprises a compound of the formula X.sup.1 (X.sup.m+1).sub.m wherein m is at least 1 and X.sup.1 through X.sup.m+1 are covalently coupled porphyrinic macrocycles. Light harvesting arrays and solar cells containing such light harvesting rods are also described, along with intermediates useful in such methods and rods produced by such methods.
Systems and methodologies are provided for forming a diode component integral with a memory cell to facilitate programming arrays of memory cells created therefrom. Such a diode component can be part of a PN junction of memory cell having a passive and active layer with asymmetric semiconducting properties. Such an arrangement reduces a number of transistor-type voltage controls and associated power consumption, while enabling individual memory cell programming as part of a passive array. Moreover, the system provides for an efficient placement of memory cells on a wafer surface, and increases an amount of die space available for circuit design.
A method of making organic memory cells made of two electrodes with a controllably conductivce media between the two electrodes is disclosed. The controllably conductive media contains an organic semiconductor layer and passive layer. The organic semiconductor layer is formed using spin-on techniques with the assistance of certain solvents.
