Abstract: A method of forming a free-standing (Al, Ga, In)N article, by the steps including: providing an expitaxially compatible sacrificial template; depositing single crystal (Al, Ga, In)N material on the template to form a composite sacrificial template/(Al, Ga, In)N article including an interface between the sacrificial template and the (Al, Ga, In)N material; and interfacially modifying the composite sacrificial template/(Al, Ga, In)N article to part the sacrificial template from the (Al, Ga, In)N material and yield the free-standing (Al, Ga, In)N article. The free-standing (Al, Ga, In)N article produced by such method is of superior morphological character, and suitable for use as a substrate, e.g., for fabrication of microelectronic and/or optoelectronic devices and device precursor structures.

Abstract: A method of forming a free-standing (Al, Ga, In)N article, by the steps including: providing an expitaxially compatible sacrificial template; depositing single crystal (Al, Ga, In)N material on the template to form a composite sacrificial template/(Al, Ga, In)N article including an interface between the sacrificial template and the (Al, Ga, In)N material; and interfacially modifying the composite sacrificial template/(Al, Ga, In)N article to part the sacrificial template from the (Al, Ga, In)N material and yield the free-standing (Al, Ga, In)N article. The free-standing (Al, Ga, In)N article produced by such method is of superior morphological character, and suitable for use as a substrate, e.g., for fabrication of microelectronic and/or optoelectronic devices and device precursor structures.

Abstract: A method of generation and detection of acoustic signals carrying alpha-numeric data for reducing the effects of noise and thereby improving signal transmission without the need to boost the power of the signal. In accordance with one aspect of the invention, a special DTMF acoustic signal consisting of a combination of two frequencies will be generated for the representation of a particular alpha-numeric character that will be similar to the standard DTMF tone. The difference between the amplitudes of both frequencies varies during the time of generation of the DTMF tone in such a way that both signals will arrive at a final destination detector, i.e., an interactive voice response board, at least for a portion of the generation time, at a relatively similar amplitude, thereby substantially increasing the probabilities of being recognized as a DTMF signal.

Abstract: The present invention provides methods and apparatus for the transmission of encrypted data along conventional telephone lines using various data transmission techniques, including known dual tone multi-frequency(DMTF) techniques. In accordance with a preferred embodiment of the invention, an exemplary apparatus for transmitting confidential information(data) comprises a portable hand-held module having the confidential data(e.g., credit card account numbers) and a predetermined encryption algorithm embedded therein. The apparatus which receives the encrypted transmission is equipped with an interface computer having decryption circuitry in which the inverse of the forgoing encryption algorithm is embedded.