Harris Corporation

Intersil Corporation

Intersil Americas Inc.

Fairchild Semiconductor Corporation

George V Rouse

Jack H Linn

James F Buller

Robert K Lowry

Craig J McLachlan

William H Speece

Stephen J Gaul

George S Bajor

Jose Avelino Delgado

John P Short

Michael G Shlepr

Jun Zeng

Michael D Church

Anthony L Rivoli

John W Butler

Donald Frank Hemmenway

Lawrence Pearce

John J Hackenberg

Paul S Reinecke

James R Zibrida

Linda S Brush

Linda Susan Brush

Timothy A Valade

Steven T Slasor

Diana Lynn Hackenberg

Roberta R Nolan-Lobmeyer

Sana Rafie

A bonded semiconductor-on-insulator substrate for an integrated circuit. The bonded semiconductor-on-insulator substrate includes a wafer, a handle wafer and an insulating bond layer. The wafer has a first layer of monocrystalline semiconductor material adjacent a first surface of the wafer. The wafer also has a second layer of undamaged by implantation monocrystalline semiconductor material adjacent a second surface of the wafer. The wafer further has a substantially planar intrinsic gettering zone of substantially pure semiconductor material and active gettering sites positioned between the first and second layers formed by implanting ions of the semiconductor material through the first layer of monocrystalline semiconductor material. The insulating bond layer bonds the handle wafer to the first surface of the wafer.

Bonded substrate for an integrated circuit containing a planar intrinsic gettering zone

A silicon-on-insulator integrated circuit comprises a handle die, a substantially continuous and unbroken silicide layer over the handle die, and a substantially continuous and unbroken first dielectric layer overlying one side of the silicide layer. A device silicon layer having an upper surface overlies the first dielectric layer, and a second dielectric layer on the handle die underlies the opposite side of the silicide layer. Interconnected transistors are disposed in and at the upper surface of the device silicon layer. A silicon-on insulator integrated circuit includes a handle die and a first dielectric layer formed on the handle die. A substantially continuous and unbroken silicide layer is formed on the first dielectric layer; the silicide layer has a controlled resistance and provides a diffusion barrier to impurities. A substantially continuous and unbroken second dielectric layer is disposed between the silicide layer and a device silicon layer, and trenches extend through the device silicon layer and silicide layer and separate the device silicon layer into islands, each having an underlying continuous silicide area. Interconnected transistors are disposed in and at an upper surface of the device silicon layer. A bonded wafer integrated circuit comprised a handle die and a homogeneous silicide layer bonded to the handle die. A device layer is bonded to the silicide layer, and interconnected transistors are disposed in and at a surface of device layer.

Bonded wafer with metal silicidation

A low temperature coefficient resistor(TCRL) has some unrepaired ion implant damage. The damaged portion raises the resistance and renders the resistor less sensitive to operating temperature fluctuations. A polysilicon thin film low temperature coefficient resistor and a method for the resistor's fabrication overcomes the coefficient of resistance problem of the prior art, while at the same time eliminating steps from the BiCMOS fabrication process, optimizing bipolar design tradeoffs, and improving passive device isolation. A low temperature coefficient of resistance resistor (TCRL) is formed on a layer of insulation, typically silicon dioxide or silicon nitride, the layer comprising polysilicon having a relatively high concentration of dopants of one or more species. An annealing process is used for the implanted resistor which is shorter than that for typical prior art implanted resistors, leaving some intentional unannealed damage in the resistor. The planned damage gives the TCRL a higher resistance without increasing its temperature coefficient. A process for fabrication of the resistor is used which combines separate spacer oxide depositions, provides buried layers having different diffusion coefficients, incorporates dual dielectric trench sidewalls that double as a polish stop, supplies a spacer structure that controls precisely the emitter-base dimension, and integrates bipolar and CMOS devices with negligible compromise to the features of either type.

BICMOS process with low temperature coefficient resistor (TCRL)

A low temperature coefficient resistor (TCRL) has some unrepaired ion implant damage. The damaged portion raises the resistance and renders the resistor less sensitive to operating temperature fluctuations A polysilicon thin film low temperature coefficient resistor and a method for the resistor's fabrication overcomes the coefficient of resistance problem of the prior art, while at the same time eliminating steps from the BiCMOS fabrication process, optimizing bipolar design tradeoffs, and improving passive device isolation. A low temperature coefficient of resistance resistor (TCRL) is formed on a layer of insulation, typically silicon dioxide or silicon nitride, the layer comprising polysilicon having a relatively high concentration of dopants of one or more species. An annealing process is used for the implanted resistor which is shorter than that for typical prior art implanted resistors, leaving some intentional unannealed damage in the resistor. The planned damage gives the TCRL a higher resistance without increasing its temperature coefficient. A process for fabrication of the resistor is used which combines separate spacer oxide depositions, provides buried layers having different diffusion coefficients, incorporates dual dielectric trench sidewalls that double as a polish stop, supplies a spacer structure that controls precisely the emitter-base dimension, and integrates bipolar and CMOS devices with negligible compromise to the features of either type.

BiCMOS process with low temperature coefficient resistor (TCRL)

A power trench MOS-gated transistor is constructed with a buried gate to source dielectric inside a gate trench region. In the innovative device, a thick oxide (grown or deposited) is used to define the height of the trench walls. A body region is initially formed by selective epitaxial growth and etch back. Source regions are formed also by selective epitaxial growth. The body is finally formed by selective epitaxial growth and etch back. The oxide is removed from the trench, the trench walls are oxidized to form a gate oxide, and doped polysilicon fills the trench to form a gate. By the formation of the source region using the spacer etch, this process simplifies the fabrication of power trench gated devices, and provides for increased contact surface area without increasing device size.

Power trench transistor device source region formation using silicon spacer

In a method for forming a bonded semiconductor-on-insulator substrate for the fabrication of semiconductor devices and integrated circuits, a surface of a wafer of a monocrystalline semiconductor material is implanted with ions of the semiconductor material a to a selected depth in the wafer to form, adjacent to the surface, an amorphous layer of the semiconductor material. The layer of amorphous semiconductor material extends to a substantially planar zone disposed at substantially the selected depth and comprising the monocrystalline semiconductor material damaged by lattice defects, i.e., end-of-range implant damage. Undamaged material below the selected depth comprises a first layer of the monocrystalline semiconductor material. The wafer is heated under conditions effective to convert the amorphous layer to a second layer of the monocrystalline semiconductor material and to coalesce the zone of damaged monocrystalline semiconductor material, thereby forming a substantially planar intrinsic gettering zone of substantially pure semiconductor material that includes active gettering sites disposed at substantially the selected depth. An insulating bond layer on one surface of a handle wafer is bonded to the surface of the wafer to form a bonded semiconductor-on-insulator substrate comprising a handle wafer, an insulating bond layer, and a device wafer of monocrystalline semiconductor material. The device wafer includes a substantially planar intrinsic gettering zone comprising substantially pure semiconductor material and including active gettering sites. The described bonded substrate is employed in the fabrication of semiconductor devices and integrated circuits.

Method for forming a bonded substrate containing a planar intrinsic gettering zone and substrate formed by said method

Pre heat-treatment processing of a silicon wafer to grow a hydrophilic oxide layer includes an initial step of contacting the wafer with a pre-clean SC-1 bath, thereby producing a silicon wafer surface that is highly particle free. After a deionized water rinse, the wafer is scoured with an aqueous solution containing hydrofluoric acid and hydrochloric acid to remove metallic-containing oxide from the wafer surface. In order to grow a hydrophilic oxide layer, an SC-2 bath (containing hydrogen peroxide and a dilute concentration of metal-scouring HCl) is used. The resulting hydrophilic silicon oxide layer grown on the surface of the silicon wafer using the combined SC-1.fwdarw.HF/HCL.fwdarw.SC-2 wafer cleaning process has a metal concentration no greater than 1.times.10.sup.9. The diffusion length of minority carriers is increased from a range on the order of 500-600 microns to a range on the order of 800-900 microns.

SC-2 based pre-thermal treatment wafer cleaning process

Low temperature wafer bonding using a chemically reacting material between wafers to form a bonded zone to bond two wafers together. Examples include silicon wafers with a silicon-oxidizing bonding liquid which also permits introduction of radiation hardening dopants and electrically active dopants as constituents of the bonding liquid. Silicon wafers also may use solid reactants which include deposited layers of metal and polysilicon to form silicide bonded zones. Oxidizers such as nitric acid may be used in the bonding liquid, and a bonding liquid may be used in conjunction with a solid bonding reactant. Dielectric layers on silicon wafers may be used when additional silicon is provided for the bonding reactions. Integrated circuits fabricated from such bonded wafers may have buried layers and radiation hardening and buried resistors.

Bonded wafer processing with oxidative bonding

A bonded wafer with a bond junction having low resistivity due to the low level of oxides at the bond junction. A plasma that removes native oxide layers from wafers is exposed to the wafers. The plasma forms a hydrophobic polymer seal on the wafers, inhibiting subsequent native oxide growth upon exposure to air. The polymer seal on the wafers to be bonded are pressed together and the wafers are annealed to form the bonded wafer in a non-oxidizing ambient. The bond junction formed is primarily silicon to silicon and silicon to carbon bonds.

Bonded wafer

Bonded wafer and method of fabrication thereof

Low temperature silicon-on-insulator wafer bonding using a silicide bond formation reaction. Dielectric isolation with silicon dioxide, diamond, silicon-nitride, and so forth yields buried resistors under trench isolated silicon islands. Buried dielectrics can be thermally susceptible films like diamond due to the low temperature of the bonding silicidation reaction. Bonding silicides also provide thermal dissipating layer between a buried diamond layer and a handle wafer for good overall thermal conductivity. Bonding silicides also act as diffusion barriers.

Bonded wafer processing with metal silicidation

Low temperature wafer bonding using a silicon-oxidizing bonding liquid permits introduction of radiation hardening dopants and electrically active dopants as constituents of the bonding liquid. Oxidizers such as nitric acid may be used in the bonding liquid. Dielectric layers on the device wafer and the handle wafer may be used when additional silicon is provided for the oxidative bonding. Integrated circuits fabricated from such bonded wafers may have buried layers and radiation hardening with device silicon too thick for implantation.

Bonded wafer processing

Low temperature silicon-on-insulator wafer bonding using a silicide bond formation reaction. Dielectric isolation with silicon dioxide, diamond, silicon nitride, and so forth yields buried resistors under trench isolated silicon islands. Buried dielectrics can be thermally susceptible films like diamond due to the low temperature of the bonding silicidation reaction. Bonding silicides also provide thermal dissipating layer between a buried diamond layer and a handle wafer for good overall thermal conductivity. Bonding silicides also act as diffusion barriers. The silicide bonding takes place in the presense of a liquid oxidizer such as aqueous solution of HNO.sub.3 and H.sub.2 O.sub.2.

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Indialantic, FL, United States of America

George V Rouse