摘要:
On the back of a wafer there are deposited firstly a gold layer and then an aluminium layer (eventually including a small silicon percent). It is finally carried out a thermic treatment at low temperature, which causes the aluminium migration towards the wafer through the gold layer.
摘要:
The microtips of charge emitting material, which define the cathode of the flat FED screen and face the grid of the screen, are tubular and have portions with a small radius of curvature. The microtips are obtained by forming openings in the dielectric layer separating the cathode connection layer from the grid layer, depositing a conducting material layer to cover the walls of the openings, and anisotropically etching the layer of conducting material to form inwardly-inclined surfaces with emitting tips. Subsequently, the portions of the dielectric layer surrounding the microtips are removed.
摘要:
A process for forming a microtip cathode structure on a field emission display panel which avoids the need of vacuum depositing a lift-off layer for the microtip deposition overstructure in specially equipped reactors to accomplish a deposition at a grazing angle, by co-patterening the lift-off layer together with an underlying metal grid layer using a succession of different etching steps through the openings of a grid definition mask. According to an embodiment, nickel is used as lift-off material and is either wet-etched or sputter-etched before performing a plasma etch of the underlying grid metal layer. According to an alternative embodiment, the masking resist layer is used as lift-off material.
摘要:
A process for forming low threshold voltage P-channel MOS transistors in semiconductor integrated circuits for analog applications, said circuits including high resistivity resistors formed in a layer of polycrystalline silicon and N-channel MOS transistors having active areas which have been obtained by implantation in a P-type well, comprises the steps of,providing a first mask over both said resistors and the semiconductor regions where the low threshold voltage P-channel transistors are to be formed,doping the polycrystalline layer uncovered by said first mask,providing a second mask for protecting the resistors and the semiconductor regions where said low threshold voltage P-channel transistors are to be formed, andN+ implanting the active areas of the N-channel transistors.
摘要:
A nonvolatile, EPROM type memory cell, formed using a p-channel MOS device instead of an n-channel MOS device as customary according to the prior art, offers several advantages: improved programming characteristics, a relatively low gate voltage for writing, a lower power dissipation and above all compatability with the great majority of CMOS fabrication processes. An explanation of such surprising characteristics may be attributed to more favorable conditions of electric field during programming, i.e. during charging of the floating gate, in respect to those existing in the case of the conventional n-channel memory cell.
摘要:
A semiconductor substrate has active areas bounded by portions of an insulating layer. A thin layer of tunnel oxide is formed on the substrate and a first layer of conductive material is then deposited. Non-volatile memory cells are manufactured thereon by defining floating gate regions. The definition of these floating gate regions involves defining the first layer of conductive material in order to form a plurality of alternated stripes above pairs of active areas alternated by active areas lacking stripes. Spacers are then formed in the shelter of the side walls of the alternated stripes. A second layer of conductive material is then deposited together with the first layer of conductive material. The spacers are then selectively removed.
摘要:
Embodiments of this invention relate to a method for manufacturing isolation structures with different depths in a monolithically integrated semiconductor electronic device. An inventive method according to an embodiment of the invention comprises a first step of defining active areas on a semiconductor material substrate, a second step of forming isolation structures by realising trenches in said substrate and then filling them with field oxide, a third step of defining lithographically at least a first device area, and a fourth step of realising a digging in the substrate and in the field oxide of said first device area.
摘要:
A high voltage capacitor, integratable monolithically on a semiconductor substrate which accommodates a field oxide region overlaid by a first layer of polycrystalline silicon isolated from a second layer of polycrystalline silicon by an interpoly dielectric layer, comprises two elementary capacitors having a first common conductive plate which is formed in the first layer of polycrystalline silicon. Each of these elementary capacitors has a second conductive plate formed in the second layer of polycrystalline silicon above the first plate, and includes said interpoly dielectric layer as an isolation dielectric between the two plates.
摘要:
A method for reducing birdbeaks formed during a planox process is disclosed. On a silicon substrate (1), oxide (2) and nitride (3) are formed. The oxide and nitride are then selectively etched using a single plasma having high selectivity with respect to silicon and a photoresist mask (4). The high selectivity toward silicon is achieved by use of a CHF.sub.3 +CO.sub.2 plasma under conditions of 30:1 oxide/silicon selectivity. Field oxide regions (5) with reduced birdbeaks can then be formed.
摘要翻译:公开了一种减少在平面过程中形成的鸟鸣的方法。 在硅衬底(1)上形成氧化物(2)和氮化物(3)。 然后使用相对于硅和光致抗蚀剂掩模(4)具有高选择性的单个等离子体来选择性地蚀刻氧化物和氮化物。 对硅的高选择性通过在30:1氧化物/硅选择性的条件下使用CHF 3 + CO 2等离子体来实现。 然后可以形成具有减小的鸟喙的场氧化物区域(5)。
摘要:
The method provides for the formation of a layer of metal silicide on the gate layer of polycrystalline silicon and, for each transistor of the CMOS pair, the simultaneous doping of the active regions and the gate polycrystalline silicon. In the structure produced by this method, the gate electrodes are of polycrystalline silicon covered by metal silicide and the gate electrode of the n-channel transistor is doped with n-type material, while the gate electrode of the p-channel transistor is doped with p-type impurities. This enables the production of low threshold voltages for both transistors even in the case of very high integration densities.