For discrete automation systems, certain human operations may violate desired safety requirements and result in catastrophic failure. For such humanin-the-loop systems, this paper proposes a systematic approach to developing supervisory agents which guarantee that manual operations meet required safety specifications. In the present approach, Petri nets (PN) are applied to construct a system mo...

Sol-gel derived lead zirconate titanate (PZT) thin films are being investigated for micromechanical applications. A synthesis technique which involves the spin coating of several thin layers followed by rapid thermal annealing to crystallize the perovskite phase and repetition to achieve thicker films is described. Methods of improving the PZT-PZT interfaces between subsequently annealed layers...

A study is made of germanium diffusion in polysilicon emitters of SiGe heterojunction bipolar transistors made by germanium implantation. Implanted Ge is found to diffuse from the single-crystal silicon substrate into deposited polysilicon emitter layers during rapid thermal anneal at 1045 °C. Measurements of germanium diffusivity in polycrystalline silicon are reported at temperatures between ...

This paper compares the use of four mechanical methods for characterization of residual stress variation in low pressure chemical vapor deposited (LPCVD) polysilicon thin films deposited, doped, and annealed under different conditions. Stress was determined using buckling structures, vibrating microstructures, static rotating structures and the wafer curvature method. After deposition of 1.0 μm...

The electrical and optical characteristics of GaN:Mg irradiated by a pulsed KrF ~248 nm! excimer laser have been studied. When an as-grown Mg-doped GaN film was irradiated by an excimer laser at an energy density of 590 mJ/cm in a nitrogen atmosphere, the hole concentration was drastically increased up to 4.42310 cm. Furthermore, a GaN:Mg thin film, which was treated by laser irradiation follow...

The heat flux distribution of an infrared halogen lamp in a Rapid Thermal Processing (RTP) equipment is studied. An overview of lamp modelling in RTP systems is given and for the first time, the infrared lamp bank is modelled by taking into consideration with accuracy a lamp portion in the bank environment. A three-dimensional (3D) lamp model, with a fine filament representation is largely pres...

It is shown that the high p-type conductivity in GaN:Mg, grown by metal-organic chemical vapor deposition followed by post-growth annealing, is due to non-equilibrium acceptor concentrations. A series of samples cut from a single GaN:Mg wafer, which initially had undergone rapid thermal annealing (RTA) after growth, has been investigated. The samples were annealed at various temperatures in nit...

The nanostructure and magnetic properties of in situ ordered polycrystalline FePt thin films ~9 nm! have been studied. Films were deposited with a MgO underlayer onto Si and glass substrates using conventional rf diode sputtering. Perpendicular anisotropy was obtained when the substrate temperature exceeded 490 °C. The maximum order parameter ~S! was estimated to be ;0.9. The coercivities (Hc) ...

WSi, thin films deposited on InP substrates have been investigated for possible use as refractory ohmic contact materials for self-aligned laser devices. The films have been rf diode sputtered using various Ar gas pressures from a single commercial target composed of W and Si with an atomic ratio of 1:l. Following the deposition, the WSiJInP samples were rapid thermal processed using a rapid th...

Acoustic techniques are used to monitor the temperature of silicon wafers in rapid thermal processing environments from room temperature to 1000" C with f 5 " C accuracy. Acoustic transducers are mounted at the bases of the quartz pins that support the silicon wafer during processing. An electrical pulse applied across the transducer generates an extensional mode acoustic wave which is guided b...