Process for the preparation of thin moncrystalline or polycrystalline semiconductor material films, characterized in that it comprises subjecting a semiconductor material wafer having a planar face to the three following stages: a first stage of implantation by bombardment (2) of the face (4) of the said wafer (1) by means of ions creating in the volume of said wafer a layer (3) of gaseous microbubbles defining in the volume of said wafer a lower region (6) constituting the mass of the substrate and an upper region (5) constituting the thin film, a second stage of intimately contacting the planar face (4) of said wafer with a stiffener (7) constituted by at least one rigid material layer, a third stage of heat treating the assembly of said wafer (1) and said stiffener (7) at a temperature above that at which the ion bombardment (2) was carried out and sufficient to create by a crystalline rearrangement effect in said wafer (1) and a pressure effect in the said microbubbles, a separation between the thin film (5 ) and the mass of the substrate (6).

Process for the production of thin semiconductor material films

An experimental technique is described for observing the effects of switching transients in digital MOS circuits that perturb analog circuits integrated on the same die by means of coupling through the substrate Various approaches to reducing substrate crosstalk (the use of physical separation of analog and digital circuits, guard rings, and a low-inductance substrate bias) are evaluated experimentally for a CMOS technology with a substrate comprising an epitaxial layer grown on a heavily doped bulk wafer Observations indicate that reducing the inductance in the substrate bias is the most effective Device simulations are used to show how crosstalk propagates via the heavily doped bulk and to predict the nature of substrate crosstalk in CMOS technologies integrated in uniform, lightly doped bulk substrates, showing that in such cases the substrate noise is highly dependent on layout geometry A method of including substrate effects in SPICE simulations for circuits fabricated on epitaxial, heavily doped substrates is developed >

Experimental Results and Modeling Techniques for Substrate Noise in Mixed-Signal Integrated Circuits

This paper shows that game theory can be used as a unifying framework to study radio resource management in a variety of wireless networks with different service criteria It focuses on infrastructure networks where users transmit to a common concentration point such as a base station in a cellular network or an access point Since most of the terminals in a wireless network are battery-powered, energy efficiency is crucial to prolonging the life of the terminals Also, in most practical scenarios, distributed algorithms are preferred over centralized ones Throughout this article it focuses on distributed algorithms with emphasis on energy efficiency A family of power control games is presented for energy-efficient resource allocation in wireless code-division multiple-access (CDMA) networks and give discussions and conclusions

Energy-Efficient Resource Allocation in Wireless Networks

A semiconductor structure includes a thin semiconductor layer fixed on an applicator or flexible support, the thin layer having an exposed surface characterized by fractured solid bridges spaced apart by cavities. A method of producing the thin layer of semiconductor material includes implanting ions into the semiconductor wafer to define a reference plane, where the ion dose is above a minimum dose, but below a critical dose so as to avoid degrading the wafer surface. The method further includes applying a thermal treatment to define a layer of microcavities and applying stress to free the thin layer from the wafer.

Method of producing a thin layer of semiconductor material

A technique for forming a film of material (12) from a donor substrate (10). The technique has a step of introducing energetic particles (22) through a surface of a donor substrate (10) to a selected depth (20) underneath the surface, where the particles have a relatively high concentration to define a donor substrate material (12) above the selected depth. An energy source is directed to a selected region of the donor substrate to initiate a controlled cleaving action of the substrate (10) at the selected depth (20), whereupon the cleaving action provides an expanding cleave front to free the donor material from a remaining portion of the donor substrate.

Controlled cleaving process

An improved apparatus and process for detecting aberrations in production process operations is provided. In one embodiment, operations of a plasma etch reactor (10) are monitored to detect aberrations in etching operations. A reference end-point trace (EPT) is defined (62) for the etch process. Regions are defined in the reference end-point trace (70) and characteristics and tolerances for each region are defined (72-80). The etcher is run and an actual EPT is obtained (82) from the running of the etcher. The actual EPT is analyzed to identify proposed regions of the actual EPT (86), and then the proposed regions of the actual EPT are matched with regions of the reference EPT (96). The system employs a series of heuristic functions in matching proposed regions of the actual EPT with regions of the reference EPT. Characteristics of the matched regions of the actual end-point trace are compared (66) with characteristics of the corresponding regions of the reference end-point trace to determine whether aberrations have occurred during the etch process. The invention provides for an improved matching and improved comparison of actual end-point traces with reference end-point traces.

Process and apparatus for detecting aberrations in production process operations

In this paper, we present the power control problem in CDMA wireless data networks in the analytical setting of noncooperative game theory. User satisfaction is represented as a net utility function, which is the difference of a strictly concave function, based on signal to interference ratio, and a cost term on user's power. A detailed analysis for the existence and uniqueness of Nash equilibrium for the above noncooperative game is presented. Next, a decentralized power control algorithm is developed which converges to the Nash equilibrium, as demonstrated by both analytical and simulation methods. The framework is then extended to the multicell case, making user utilities depend on base-station assignment as well as powers. We propose a generalized algorithm that can handle base station assignment and hand-off, as well as power control, and study by extensive simulations its performance in a dynamic environment.

Game theoretic approach to power control in cellular CDMA

A tungsten silicide interconnect (28) is formed on device (14) as a local interconnect between devices. The tungsten silicide interconnect (28) provides several advantages over prior art methods, such as titanium nitride or polysilicon local interconnects.

Local interconnect using a material comprising tungsten

A number of communication applications are moving to digitally motivated architectures for their radio frequency module. This includes GSM-EDGE, WLAN, Bluetooth, GSM-GPRS, WiMAX. The All Digital PLL(ADPLL) forms the core of this architecture. The objective of the ADPLL is to generate a clean carrier frequency ƒ c , based on a input reference frequency ƒ ref . As part of the phase error measurement of the PLL, a Time to Digital converter(TDC) is used to measure the delay between ƒ ref clock edge and carrier clocking edge. An inverter chain is used to measure this delay as a integer number of basic inverter delay. This measurement error is termed TDC quantization error and effects the phase noise present in the final carrier. Due to the coarse delay of the basic inverter available, TDC introduces large quantization noise at the output of the PLL. This is too high for systems operating at high carrier frequencies or systems which have a tight phase noise requirement. This paper presents techniques to improve TDC quantization noise.

Quantization noise improvement of Time to Digital converter (TDC) for ADPLL

A wireless device in a wireless network transmits a data frame even in the presence of in-band interference (from transmission of other devices) on a shared channel provided in the wireless network. In an embodiment, configuration data is provided to the wireless device indicating whether frames be transmitted (stomped) or not in the presence of such inband interference. If the configuration data indicates that the wireless device transmit in the presence of in-band interference, the wireless device transmits a frame if the transmitter of the interfering communication is determined to be from a different basic service set (BSS).

Sarma S. Gunturi

Papers

Process and apparatus for detecting aberrations in production process operations

Game theoretic approach to power control in cellular CDMA

Local interconnect using a material comprising tungsten

Quantization noise improvement of Time to Digital converter (TDC) for ADPLL

Throughput performance in the presence of in-band interference in a csma based network