Abstract: A method of monitoring and displaying health performance of an aircraft engine is disclosed. The method comprises the steps of: (a) sensing engine parameters at operable positions of the aircraft engine; (b) recording and generating continuous output signals reflective of the current behavior of the aircraft engine; (c) comparing said output signals with a set of predetermined reference signals to determine if each individual parameter is operating in the safe or danger region; (d) providing an indication of the engine parameter if it is in the danger region; and (e) simultaneously displaying all representative values of the health parameters in a digital and graphical form. The output signals are displayed on a multi-function display and are displayed in a qualitative form. Two different layouts are presented, that is, the bar format and the dial format. Visual effects to give an intuitive display are greatly enhanced through the use of colors and changes in the display format.

Abstract: A novel method of forming a first polysilicon gate tip (poly-tip) for enhanced F-N tunneling in split-gate flash memory cells is disclosed. The poly-tip is formed in the absence of using a thick polysilicon layer as the floating gate. This is made possible by forming an oxide layer over the poly-gate and oxidizing the sidewalls of the polygate. Because the starting thickness of polysilicon of the floating gate is relatively thin, the resulting gate beak, or poly-tip, is also necessarily thin and sharp. This method, therefore, circumvents the problem of oxide thinning encountered in scaling down devices of the ultra large scale integration technology and the fast programmability and erasure performance of EEPROMs is improved.

Abstract: A method for forming alignment marks are disclosed for performing photoalignment after chemical-mechanical polishing (CMP). A trench is first formed in a silicon substrate and then alignment marks are formed at the bottom of the trench. The aspect ratio of the trench is selected to be so low that the dishing of the CMP pad can be prevented from reaching into the trench to damage the alignment marks therein. A trench structure is also provided whereby the alignment marks can be protected from the abrasive action of the CMP. Steps subsequent to the CMP can therefore proceed unimpeded with the presence of undamaged alignment marks.

Abstract: A plasma damage protection cell using floating N/P/N and P/N/P structure, and a method to form the same are disclosed. Floating structures of the protection cell and the floating gates for the MOS devices are formed simultaneously on a semiconductor substrate having shallow trench isolation. The floating structures are implanted separately to form the N/P/N and P/N/P bipolar base, emitter and collector regions while the source/drain of the respective NMOS and PMOS devices are implanted with appropriate sequencing. The floating structures are connected to the substrate with appropriate polarity to provide protection at low leakage current levels and with tunable punch-through voltages.

Abstract: A method of forming a boron carbide layer for use as a barrier and an etch-stop layer in a copper dual damascene structure, and the structure itself are disclosed. In addition to providing a good barrier to copper diffusion, good insulating properties, high etch selectivity with respect to dielectric insulators, boron carbide also provides good electrical characteristics because of its low dielectric constant of less than 5. The amorphous boron carbide is formed in a PECVD chamber by introducing a boron source gas such as B2H6, B5H9+, and carbon source gas such as CH4 and C2H6 at a deposition temperature of about 400° C. Any one, or any combination of the passivation, etch-stop, cap layers of the damascene structure can comprise boron carbide.

Abstract: A modified nitride spacer and making of the same are disclosed. The modified nitride spacer is formed adjacent a high-temperature oxide (HTO) layer which in turn is formed adjacent the sidewalls of a gate electrode. It is shown that the placement of an intervening oxide layer between the sidewalls of the gate electrode and the nitride spacer, in that order only, provides a significant improvement in charge retention in floating gate memory cells. Also, forming of the spacer from pure, undoped oxide only yields the same favorable results.

Abstract: A method is disclosed for forming a split gate flash memory cell having a thin floating gate and a sharp poly tip in order to improve the erasing and programming speed of the cell. The method involves the use of an oxide other than the poly oxide that is conventionally employed in forming the floating gate, and also using to advantage a so-called “smiling effect” which is normally taught away. The smiling effect, or an uneven thickening of an oxide layer, comes into play while growing interpoly oxide where concurrently the oxidation of the polysilicon gate advances in such a manner so as to form a sharp and reliable poly tip. The invention is also directed to providing a split gate flash memory cell having a thin floating gate and a poly tip therein.

Abstract: A method for preventing gate oxide damage caused by post poly definition implantation is disclosed. It is shown that the antenna ratio that is correlatable to oxide damage can be reduced and made to approach zero by implementing a mask layout during ion implantation. This involves covering all of the polysilicon electrodes with a photoresist mask, and reducing the effective antenna ratio to zero, and performing ion implantation to form source/drain regions thereafter. In this manner, the dependency of ion implantation to pattern sensitivity is also removed.

Abstract: A method is disclosed to improve copper barrier and adhesion properties of copper interconnections in integrated circuits. It is shown that combining ion metal plasma (IMP) deposition along with in-situ chemical vapor deposition (CVD) of barrier and adhesion materials provides the desired adhesion of and barrier to diffusion of copper in damascene structures. IMP deposition is performed with tantalum or tantalum nitride while CVD deposition is performed with a binary or a ternary compound from a group consisting of titanium nitride, tungsten nitride, tungsten silicon nitride, tantalum silicon nitride, titanium silicon nitride. IMP deposition provides good adhesion of copper to insulator materials, while CVD deposition provides good sidewall coverage in a copper filled trench and a copper seed layer provides good adhesion of bulk copper to adhesion/barrier layer. The IMP/CVD deposited adhesion/barrier layer is thin, thus providing low via resistance.

Abstract: A method is disclosed to form a shallow trench isolation (STI) without reverse short channel effect. This is accomplished by forming oxidized polysilicon spacers in the dielectric layers above the trench, while also employing a thermal oxide liner on the inside walls of the trench in the substrate. The polyoxide spacers and the thermal oxide liner together prevent the undercutting at the corners or shoulders of the trench, thereby avoiding the common problem of having reverse short channel effect.

Abstract: A method is provided for forming buried source line in semiconductor devices. It is known in the art to form buried contacts on the surface of a semiconductor substrate. The present invention discloses a method of fabricating a semiconductor device, particularly a memory cell, having both the source region and the source line buried within the substrate. The source line is formed in a trench in the substrate over the source region. The trench walls are augmented with voltage anti-punch-through protection. The trench also provides the attendant advantages of extended sidewall area, smaller sheet resistance, and yet smaller cell area, therefore, smaller chip size, and faster access time as claimed in the embodiments of this invention. The buried source disclosed here is integrated with source line which is also buried within the substrate.

Abstract: A method is disclosed to improve copper process integration in the forming copper interconnects in integrated circuits. This is accomplished by integrating the process of forming a copper seed layer in an interconnect structure such as a trench or a groove, with the process of plasma cleaning of the structure prior to the electroplating of copper into the trench. NH3 plasma can be used for this purpose. Or, H2/N2 thermal reduction can also be employed. The integrated process promotes well-controlled electro-chemical deposition (ECD) of copper for solid filling of the trench.

Abstract: A novel method of forming a polysilicon gate tip (poly tip) for enhanced F-N tunneling in split-gate flash memory cells is disclosed. The poly tip is further enhanced by forming a notched nitride layer over the tip. At the same time, a method of forming a self-aligned source (SAS) line is disclosed. A relatively thin polygate is formed so as to decrease the growth of the protrusion of conventional gate bird's beak (GBB) to a smaller and sharper tip. It will be known by those skilled in the art that GBB is easily damaged during conventional poly etching where polyoxide is used as a hard mask. To use polyoxide as a hard mask, thick polysilicon is needed in the first place. Such thick poly will increase gate coupling ratio, which has the attendant effect of degrading program and erasing performance of the memory cell.

Abstract: A split-gate flash memory cell having a three-dimensional source capable of three-dimensional coupling with the floating gate of the cell, as well as a method of forming the same are provided. This is accomplished by first forming an isolation trench, lining it with a conformal oxide, then filling with an isolation oxide and then etching the latter to form a three-dimensional coupling region in the upper portion of the trench. A floating gate is next formed by first filling the three-dimensional region of the trench with polysilicon and etching it. The control gate is formed over the floating gate with an intervening inter-poly oxide. The floating gate forms legs extending into the three-dimensional coupling region of the trench thereby providing a three-dimensional coupling with the source which also assumes a three-dimensional region. The leg or the side-wall of the floating gate forming the third dimension provides the extra area through which coupling between the source and the floating gate is increased.

Abstract: A method is provided for forming dual damascene structures with a partial hard mask through a judicious use of partial opening or etching of the mask which simplifies the dual damascene process, and makes it especially suitable for low-k dielectric materials in advanced sub-micron technologies capable of forming features approaching less than 0.10 micrometers (&mgr;m). This is accomplished by forming a hard mask over a low-k dielectric layer. The hard mask is first opened partially to form a trench, and later again to form a via opening. The via opening is next extended into the low-k dielectric layer, followed by etching further the partial trench into the hard mask, and then transferring the trench pattern into the dielectric layer while at the same time extending the via opening to the underlying metal layer.

Abstract: A method of forming amorphous silicon spacers followed by the forming of metal nitride over the spacers in a copper damascene structure -single, dual, or multi-structure- is disclosed in order to prevent the formation of fluorides in copper. In a first embodiment, the interconnection between the copper damascene and an underlying copper metal layer is made by forming an opening from the dual damascene structure to the underlying copper layer after the formation of the metal nitride layer over the amorphous silicon spacers formed on the inside walls of the dual damascene structure. In the second embodiment, the interconnection between the dual damascene structure and the underlying copper line is made from the dual damascene structure by etching into the underlying copper layer after the forming of the amorphous silicon spacers and before the forming of the metal nitride layer.

Abstract: A method is provided for forming a split-gate flash memory cell having a shallow trench isolation without the intrusion of a “smiling” gap near the edge of the trench encompassing the first polysilicon layer. This is accomplished by forming two conformal layers lining the interior walls of the trench. An exceptionally thin nitride layer overlying the first conformal oxide layer provides the necessary protection during the oxidation of the first polysilicon layer so as to prevent the “smiling” effect normally encountered in fabricating ultra large scale integrated circuits.

Abstract: A method of forming a boron carbide layer for use as a barrier and an etch-stop layer in a copper dual damascene structure, and the structure itself are disclosed. In addition to providing a good barrier to copper diffusion, good insulating properties, high etch selectivity with respect to dielectric insulators, boron carbide also provides good electrical characteristics because of its low dielectric constant of less than 5. The amorphous boron carbide is formed in a PECVD chamber by introducing a boron source gas such as B2H6, B5H9+, and carbon source gas such as CH4 and C2H6 at a deposition temperature of about 400° C. Any one, or any combination of the passivation, etch-stop, cap layers of the damascene structure can comprise boron carbide.

Abstract: A method is provided to improve the control of bird's beak profile of poly in a split gate flash memory cell. The control of the bird's beak profile is achieved in a first embodiment where the polycrystalline layer of the floating gate is annealed at a high temperature. The annealing promotes small grain size and hence smoother surface in the polysilicon, which in turn promotes sharper poly tip. The smoother poly surface also results in thinner inter-poly between the floating gate and the control gate, which together with the sharp poly tip, enhances the erase speed of the split-gate flash memory cell. In a second embodiment, the performance is further enhanced by providing an amorphous silicon for the floating gate, because the amorphous nature of the silicon yields a very smooth surface. This smooth surface is transferred to the recrystallized state of the silicon layer through annealing. Thus, a good control for the bird's beak is achieved.

Abstract: A new method of forming a dual damascene interconnect is disclosed for manufacturing semiconductor substrates. A contact/via hole is first formed in a first dielectric layer formed over a substructure of a substrate having devices formed therein and/or metal layers formed thereon. The contact/via hole is filled with a protective material prior to forming a second dielectric layer. Conductive line opening is formed in the second dielectric layer and over the contact/via hole having the protective material in it. The protective material protects the edge of the contact/via hole from damage due to the second etching of the conductive line opening. Thus, a dual damascene structure is disclosed wherein the integrity of the edge of the contact/via hole is preserved, avoiding any reliability problems in the semiconductor product.