RU-2860255-C9 - METHOD FOR NON-VOLATILE ACOUSTOELECTRONIC INFORMATION ENCODING

Abstract

FIELD: electricity. SUBSTANCE: use: for creating non-volatile data storage devices. essence of the invention lies in that a method for non-volatile acoustoelectronic information encoding includes: a) applying, onto a semiconductor layer/piezoelectric heterostructure, ohmic contacts in the form of an interdigitated transducer (IDT1) with a period Λ=2λ_SAW twice as large as the spatial period of an excited surface acoustic wave (SAW), and a number of electrodes N1 necessary for self-excitation of IDT1 to transition it into a monolithic parametric SAW generator (MPSG) mode; b) applying, at a distance L0 in the same acoustic channel, a second similar transducer (IDT2) electrically connected in series with IDT1, with a number of electrodes N2 at which self-excitation of IDT2 is impossible; c) connecting an electrical input to a common signal bus (CSB) of transducers IDT1 and IDT2 - for supplying, only in interrogation mode, a clock rectangular direct current pulse by connecting the CSB to a direct current source creating a spatially periodic electric field in the semiconductor layer; d) connecting an output electrical resistance R_load to IDT2 to form logic states: binary code at R_load={0, RL0} or ternary state code '0,+1,-1' depending on R_load and the distance L between IDT1 and IDT2, where L takes two values differing by λ_SAW/2. EFFECT: enabling reduction of power consumption, increasing noise immunity. 1 cl, 4 dwg

Inventors

• SVESHNIKOV BORIS VLADIMIROVICH

Dates

Publication Date

20260506

Application Date

20250829

Claims (1)

1. A method for non-volatile acoustoelectronic encoding of information, comprising: a) applying ohmic contacts to a "semiconductor layer/piezoelectric" heterostructure in the form of an interdigital transducer (P1) with a period Λ=2 λ_SAW, twice as large as the spatial period of the excited surface acoustic wave (SAW), and a number of electrodes N1 required for self-excitation of P1, for its transition to the mode of a monolithic parametric SAW generator (MPG); b) applying - at a distance L0 in the same acoustic channel, electrically connected in series with P1, a second similar transducer (P2) with a number of electrodes N2, at which self-excitation of P2 is impossible; c) connection to the common signal bus (CSB) of converters P1 and P2 of the electrical input - to supply only in the polling mode of the clock rectangular pulse of direct current by connecting the CS to a source of direct current, which creates a spatially periodic electric field in the semiconductor layer; d) connection to P2 of the output electrical resistance R_load to form logical states depending on R_load and the distance L between P1 and P2, where L takes two values that differ from each other by the value λ_SAW/2: binary code when R_load={0,RL0} or ternary code - "0", "+1", "-1" - when L={L1,L2} and L1–L2=λ_SAW/2.

Description

Field of technology The invention relates to non-volatile methods for storing coded information using phase manipulation (PM) based on surface acoustic waves (SAW) and can be used • when creating static and dynamic computer memory media; • in digital assessment systems (DAS); • in neuromorphic computing (phase coding → analogy with synapses, multi-valued logic → increasing network complexity); • in cryptography (quasi-random SAW signals + FM = stable keys). Prior art The widespread development of artificial intelligence systems requires enormous energy consumption, the bulk of which is associated with storing exponentially growing volumes of data. The fact is that virtually all modern logic gates (TTL, NMOS, CMOS, etc.) that encode the required information require external power sources. This applies not only to static but also to dynamic digital memory. Static random access memory (SRAM) maintains a writable state (see, e.g., [1]) while power is present, and all information is erased as soon as the external power source is disconnected. Dynamic random access memory (DRAM) physically consists of cells created in a semiconductor material as a capacitance (see, e.g., [2]). A charged or discharged cell stores a bit of data. Each cell of such memory tends to discharge (due to leakage currents, etc.), so it must be constantly recharged, as processes are constantly occurring within it that change its state, even when it is not being accessed. Passive electronic elements called memristors, which have recently gained recognition, can serve as non-volatile memory cells (see, for example, [3]). When off, a memristor consumes no energy, has high switching speed, and possesses memory: when the voltage across the memristor is zero, its resistance remains the same as when the voltage was removed. However, the manufacture of memristors is accompanied by insufficiently reliable reproducibility of their characteristics (both from sample to sample and from cycle to cycle of logical state switching). The method of acoustoelectronic encoding of information using logic gates (LV) of a new type proposed in this application eliminates the problems described above: firstly, the information in the code cells of the new type will be stored indefinitely even without external power supply and will be read at the required time using only a short-term connection of a stationary current source to the code cells, and secondly, the reproducibility of the characteristics of the planar topology of the manufacture of multi-electrode structures and semiconductor films with a given doping level required for the implementation of this method is a key advantage of modern microelectronics. The essence of the invention Physical principle of monolithic parametric amplification (MPA) The effect is based on the generation of SAW in the structure "piezoelectric - semiconductor layer with a finite thickness (h)" with spatial modulation of the DC field (E o (x) with a period Λ=2λ_SAW. Such modulation is created using a multi-electrode system of ohmic contacts (3) on the surface of the semiconductor layer (SL) made in the form of an interdigital transducer (IDT) with the number of electrodes N, connected to an external source of direct current (EMF). The frequency of acoustic synchronism of the IDT is half the SAW frequency (f0_IDT=v_SAW/Λ=f0/2, where v_SAW is the SAW velocity), i.e. in the absence of the SL (h=0) the acoustic impedance (RT) of the transducer at a frequency f0 is zero: RT=0 at h=0. Figure 1 represents the general diagram of a monolithic parametric amplifier (a) and its two partial circuits as circuits of direct (b) and alternating (c) currents: Ip=Ep/(rS+rEL) is the direct pump current (which corresponds to the pump voltage and Ic is the high-frequency signal current in a closed circuit formed by: 1) the internal resistance of the EMF rS, 2) the resistance rEL of the interelectrode gaps of the PS, 3) the reactive load Z0 added to increase the amplification efficiency, 4) the static capacitance of the IDT C0 and 5) its acoustic impedance RT. The quadratic nonlinearity of the PS plasma ensures the interaction of the primary space charge waves (SPW) (k=2π/λ_SAW, ω=2π⋅f0), induced in the PS by the wave incident on the IDT, and the direct current flowing through the ohmic contacts of the IDT in a stationary field As a result, secondary VZs arise. where q=k/2, inducing a high-frequency current Ic(ω) in the circuit formed by the IDT and the LC circuit. Since the total voltage drop in a closed AC circuit without high-frequency sources is zero, the total impedance of this circuit is also zero. Consequently, in the system under consideration, negative resistance necessarily arises in the idle circuit: Re(RT)<0 for h>0. This means not only amplification of the wave incident on the IDT (with amplitude U0), but also the appearance of a reflected SAW, the amplitude of which can also become greater than the amplitude U0 at a sufficient value of Vp. Phys