Abstract: An improved integrated circuit structure characterized by enhanced step coverage and a method of making it are disclosed. The structure comprises a base layer of silicon, a first oxide layer on the silicon layer, strips of poly silicon having selected portions thereof reacted with a metal capable of forming a metal silicide in situ on the surface of the poly silicon strips, a further oxide layer over the metal silicide, and a metal layer providing electrical contact to selected portions of the structure. The construction makes it possible to remove all of an intermediate oxide layer during manufacture except for an oxide layer above the poly load resistor. This elimination of one oxide layer, together with the integration of the conductive metal silicide and underlying poly silicon into one layer and the rounding of the metal silicide edge with oxide spacers via anisotropic etching of the intermediate oxide layer, permits better step coverage for the resulting structure.
Abstract: A CMOS static RAM, which has P channel transistors formed in a second polysilicon layer, N channel transistors formed in the substrate, and gates of both the N channel and P channel transistors formed in a first polysilicon layers, requires that ohmic contact be made between semiconductor material of differing conductivity type. The first polysilicon layer is N-type, and the second polysilicon layer is P-type. Ohmic contact therebetween is achieved by providing a silicide layer which is between these two layers and in physical contact with both. Ohmic contact between N-type regions in the substrate and the second polysilicon layer is similarly achieved by sandwiching silicide therebetween.
Abstract: A method is set forth for forming conductive contacts to first, second and third regions of a substrate. The substrate is covered with an insulating layer having a slot with an island therein. The island is covered with a first sacrificial layer. The substrate is covered with a conformal coating of a dielectric material. The coating is etched off with retention of sacrificial portions of the dielectric material between the island and the insulating layer. The first sacrificial layer is removed from the island while the sacrificial portions remain. A conductive layer is deposited upon the substrate. A second sacrificial layer is laid down upon the conductive layer. The second sacrificial layer is etched away along with the sacrificial portions of the dielectric material while the conductive layer is not significantly removed. Highly conductive contacts are provided with the conductive material self-aligned on the source, drain and gate.
Abstract: An MOS device having a gate electrode and interconnect of titanium nitride and especially titanium nitride which is formed by low pressure chemical vapor deposition. In a more specific embodiment the titanium nitride gate electrode and interconnect have a silicon layer thereover to improve oxidation protection.
Type:
Grant
Filed:
March 7, 1983
Date of Patent:
February 18, 1986
Assignee:
Motorola, Inc.
Inventors:
J. B. Price, Philip J. Tobin, Fabio Pintchovski, Christian A. Seelbach
Abstract: A thin conducting line such as a gate pattern is defined on a semiconductor chip (10) by applying a narrow ion beam, suitably a focused-ion-beam (16) having a submicrometer thickness from a source (18) onto a thin layer (14) of an inorganic material such as silicon or aluminum overlying a layer (12) of refractory metal on a substrate (11). The ion beam is translated to form a gate pattern at a dose between about 0.1 to 50.times.10.sup.15 cm.sup.-2 and an energy from about 1 to 1000 KeV. Ions are implanted into the silicon and aluminum layers and into the underlying portions of the refractory metal layer and to render the exposed portions of the layers preferentially resistant to wet-etchant. The portions of layers which are not exposed nor protected by layers which are exposed, are preferentially removed to form a gate. Conventional MOSFET or MESFET processing to implant ions to form source and drain regions may then be performed.
Abstract: A method of manufacturing stable, low resistance contacts in an integrated semiconductor circuit which involves providing highly doped impurity diffused regions in a silicon substrate, forming a silicon dioxide layer over the highly doped diffused regions and the surrounding substrate, forming contact holes of uniform size in the silicon dioxide layer in selected areas of the highly doped diffused regions, applying a layer including a metal silicide into the holes in contact with the underlying highly doped diffused regions, applying an n.sup.+ -doped polysilicon layer into the contact holes and over the silicon dioxide layer with a thickness corresponding to about half the contact hole side length, and then depositing a layer of predominantly aluminum over the n.sup.+ -doped polysilicon layer.
Abstract: The present invention relates to a method of forming a diffused region with a shallow junction having a refractory metal silicide layer thereon. At first, the refractory metal silicide layer is selectively formed on a silicon substrate of one conductivity type. An insulating film is then formed at least on the refractory metal silicide layer, and a contact hole is opened on a part of the silicide layer. After necessary high temperature treatments have been conducted, a dopant impurity of the opposite conductivity type is introduced from the contact hole to the silicide layer. The impurity is laterally dispersed in the silicide layer and diffused into the whole portion of the silicon substrate in contact with the silicide layer, whereby the diffused region with a shallow junction can be formed.
Abstract: Disclosed is a method of making ohmic and/or Schottky barrier contacts to a silicon semiconductor substrate in which before depositing the metal on silicon semiconductor substrates containing integrated circuits which are covered by a mask having contact windows, the metal is initially deposited on freshly cleaned blank silicon semiconductor substrates mounted in the same vacuum chamber. In this manner any traces of oxygen present in the vacuum chamber are chemisorbed by the blank substrate resulting in deposition of a high quality oxide-free metal contacts on the device substrates.
Type:
Grant
Filed:
December 23, 1983
Date of Patent:
October 8, 1985
Assignee:
International Business Machines Corporation