Abstract: A method, apparatus, and circuit distribution wafer (CDW) (16) are used to wafer-level test a product wafer (14) containing one or more product integrated circuits (ICs). The CDW (16) contains circuitry which is used to test the ICs on the product wafers (14). A connection from the product wafer (14) to the CDW (16) is made via a compliant interconnect media (IM) (18). Through IM (18), the CDW (16) tests the product wafer (14) under any set of test conditions. Through external connectors and conductors (20, 22, 24, and 26) the CDW (16) transmits and receives test data, control information, temperature control, and the like from an external tester (104). To improve performance and testability, the CDW (16) and heating/cooling (80 and 82) of the wafers may be segmented into two or more wafer sections for greater control and more accurate testing.

Abstract: A method for forming an improved copper inlaid interconnect (FIG. 11) begins by performing an RF preclean operation (408) on the inlaid structure in a chamber (10). The RF preclean rounds corners (210a and 206a) of the structure to reduce voiding and improve step coverage while not significantly removing copper atoms from the underlying exposed copper interconnects surfaces (202a). A tantalum barrier (220) is then deposited where one portion of the tantalum barrier is more tensile than another portion of the tantalum barrier. After formation of the barrier layer (220), a copper seed layer (222) is formed over a top of the barrier layer. The copper layer is formed while clamping the wafer with an improved clamp (85) which reduces copper peeling and contamination at wafer edges. Copper electroplating and chemical mechanical polishing (CMP) processes are then used to complete the copper interconnect structure.

Abstract: A lithographic mask (FIG. 9 or FIG. 10) that is primarily used for SCALPEL processing has a substrate (100). Layers (102, 104, 106, 108, 110, and 112) are formed and selectively patterned and etched to form E-beam exposure windows (118) and skirt regions (120) framing the windows (118). The skirt regions (120) and some portions of the patterned features (124) within the window (118) are formed having thicker/thinner regions of material or formed of different material whereby different regions of the mask (FIG. 9) scatter energy to differing degrees. The different scattering regions on the mask allow SCALPEL patterns to be formed on the wafer with improved critical dimension (CD) control, reduced aberrant feature formation, and improved yield.

Abstract: A split-gate EEPROM transistor includes a channel region (22) formed in a vertically disposed semiconductor body (58) and residing intermediate to a drain region (26) and a source region (24). A select gate electrode (28) is horizontally disposed on a semiconductor substrate (20). A floating gate electrode (30) resides adjacent to the channel region (22) and overlies the select gate electrode (28). A control gate electrode (32) resides adjacent to the control gate electrode (30) and also overlies the select gate electrode (28). In operation, the select gate electrode (28) regulates the flow of electrical charge from the source region (24) into the channel region (22), and provides a field plate electrical isolation for adjacent memory cells in an EEPROM array.

Abstract: A method for forming void free tungsten plug contacts (56a-56c) begins by etching a contact opening (55a-55c) using a C2F6 and CHF3 chemistry. The etch chemistry is then changed to an O2 and CH3F chemistry in order to insitu remove the contact photoresist while tapering an upper portion of the contact opening. A tungsten deposition process is then performed whereby the tapered portion of the contact reduces the effects of nonconformal and step-coverage-inconsistent tungsten deposition wherein voids in the contact are either substantially reduced or totally avoided within the contact structure. The reduction of or total elimination of voids (22) within the tungsten contact will increase yield, increase reliability, and reduce electromigration failures within integrated circuit devices.

Abstract: A dual inlaid copper interconnect structure uses a plasma enhanced nitride (PEN) bottom capping layer and a silicon rich silicon oxynitride intermediate etch stop layer. The interfaces (16a, 16b, 20a, and 20b) between these layers (16 and 20) and their adjacent dielectric layers (18 and 22) are positioned in the stack (13) independent of the desired aspect ratio of trench openings of the copper interconnect in order to improve optical properties of the dielectric stack (13). Etch processing is then used to position the layers (16) and (20) at locations within the inlaid structure depth that result in one or more of reduced DC leakage current, improved optical performance, higher frequency of operation, reduced cross talk, increased flexibility of design, or like improvements.

Abstract: A method for electroplating a copper layer (118) over a wafer (20) powers a cathode of an electroplating system (10) in a manner that obtains improved copper interconnects. A control system (34) powers the cathode of the system (10) with a mix of two or more of: (i) positive low-powered DC cycles (201 or 254); (ii) positive high-powered DC cycles (256 or 310); (iii) low-powered, pulsed, positive-power cycles (306 or 530); (iv) high-powered, pulsed, positive-powered cycles (212, 252, 302, or 352); and/or (v) negative pulsed cycles (214, 304, 510, 528, or 532). The collection of these cycles functions to electroplate copper or a like metal (118) onto the wafer (20). During electroplating, insitu process control and/or endpointing (506, 512, or 520) is performed to further improve the resulting copper interconnect.

Abstract: A method for forming a tantalum-based anti-reflective coating (ARC) layer begins by forming an MOS metallic gate electrode layer (20) over a substrate (20). The MOS metallic gate electrode layer (20) is covered with an ARC layer (22). The ARC layer is preferably tantalum pentoxide or a tantalum pentoxide layer doped with one or more of nitrogen atoms and/or silicon atoms. The layers (22 and 20) are then selectively masked photoresist (24) that is selectively exposed to deep ultraviolet (DUV) radiation (28). The ARC layer (22) improves lithographic critical dimension (CD) control of the MOS metallic gate during exposure. The final MOS metallic gate is then patterned and etched using a fluorine-chlorine-fluorine time-progressed reactive ion etch (RIE) process, whereby metallic-gate MOS transistors are eventually formed.

Abstract: A method for forming a copper interconnect begins by depositing a barrier layer (48) within an in-laid region (18). An edge exclusion protection layer (50) is formed over the barrier layer (48), and this layer (50) is processed so that it only lies within the edge exclusion region (20) of the wafer. The layer (50) is removed from active area portions of the wafer so that contact resistance of copper interconnects is not affected. Wet surface processing is used to form a catalyst (64b) on the wafer surface to enable electroless copper plating within active areas of the wafer to form a copper seed layer (52). The layer (52) is not formed in an edge exclusion region (20). Electroplating is then used to thicken the copper material to form a copper layer (54) over the layer (52) wherein the in-laid copper interconnect is completed.

Abstract: A method for forming an embedded DRAM integrated circuit (10) begins by forming an asymmetric source and drain structure on the DRAM pass transistors. The asymmetric DRAM transistor structure has a lightly doped shallow current electrode (60) that connects to a trench capacitor (30, 28, and 24). The bit line current electrode of the DRAM pass transistor is formed having an LDD region (60) and an adjacent highly doped drain region (76). The region (76) helped to improve DRAM data retention reliability. In addition, the current electrode connected to the bit line is silicided to form a silicide region (80) which has improved coupling to an overlying tungsten plug (84). In addition, a P-type halo implant (78) is used to reduce or eliminate adverse short channel effects within a DRAM device.

Abstract: A method for forming a buried optical mirror in an integrated circuit (IC) begins by forming an opening (18) within a substrate (12). The opening (18) is then filled with a plurality of dielectric layers (20-26) that have different indexes of refraction whereby a Bragg reflector can be formed. A chemical mechanical polishing (CMP) process is then used to planarize the layers (20-26) such that these layers (20-26) only reside within the opening (18) whereby a mirror is formed. Lateral selective epitaxial growth, polysilicon deposition and recrystallization, or wafer bonding is then used to form a single crystalline or near single crystalline semiconductive material (32b) over a top of the substrate (12) and the reflecting mirror. Photodevice(s) are then formed over the mirror in the region (28) of material (32b) whereby reflecting mirror (20-26) will improve the quantum efficiency and speed of the photodevice(s).

Abstract: A method for forming a capped shallow trench isolation (CaSTI) structure begin by etching a trench opening (210). The opening (210) is filled with an oxide or like trench fill material (216b) via a deposition and chemical mechanical polish (CMP) step. The plug (216b) is reactive ion etched (RIE) to recess a top of the plug (216b) into the trench opening (210) to form a recessed plug region (216c). A silicon nitride or oxynitride capping layer (218b) is then formed over the recessed plug region (216c) via another deposition and polishing step. The nitride cap layer (218b) protects the underlying region (216c) from erosion due to active area preparation, cleaning, and processing.

Abstract: A method for forming a gate dielectric having different thickness begins by providing a substrate (12). A sacrificial oxide (14) is formed overlying the substrate (12). A first portion (11) of the sacrificial oxide (14) is exposed to a carbon-containing plasma environment (20). This carbon-containing plasma environment (20) forms a carbon-containing layer (24) within the region (11). After forming this region (24), a wet etch chemistry (22) is used to remove remaining portions of the sacrificial oxide (14) without forming a layer (24) in the region (13). Furnace oxidation is then used to form regions (26a) and (26b) wherein the growth of region (26a) has been retarded by the presence of the region (24). Therefore, the regions (26a) and (26b) are differing in thickness and can be used to make different transistors having different current gains.

Abstract: A method for forming an improved copper barrier layer begins by providing a silicon-containing layer (10). A physical vapor deposition process is then used to form a thin tantalum nitride amorphous layer (12). A thin amorphous titanium nitride layer (14) is then deposited over the amorphous tantalum nitride layer. A collective thickness of the tantalum nitride and titanium nitride layers 12 and 14 is roughly 400 angstroms or less. A copper material 16 is then deposited on top of the amorphous titanium nitride wherein the composite tantalum nitride layer 12 and titanium nitride layer 14 effectively prevents copper from diffusion from the layer 16 to the layer 10.

Abstract: A differential line driver circuit has a first operational amplifier (202) and a second operational amplifier (204). The operational amplifiers use resistors (214a, 214b, 218a, and 218b) to translate to the input voltages (206 and 208) to output voltages and VOP and VON. Feedback paths containing resistors (216a and 216b) are used to monitor output conditions whereby impedance may be actively synthesized within the operational amplifiers (202 and 204). The combination of the synthesized impedance within the operation amplifiers (202 and 204) and the physical resistance of the elements (220a and 220b) are sufficient to match the line resistance (222) of a communication line. While obtaining impedance matching in accordance with required specifications, the synthesized impedance will allow for the line driver (200) to operate with significantly reduced power consumption.

Abstract: According to the present invention, an LFSR (300) has a propagation path (30) of serially coupled stages (65) and gates (80-3, 80-4), a feedforward path (10) of gates (80-1) and a feedback path (20) of gates (80-2). Depending on control signals (P, B, M), the gates (80-1, 80-2, 80-3, 80-4) are either active gates and operate as xor-gates or passive gates and operate as transfer gates. Feedforward and feedback signals are derived from input and output signals and can be supplied to any stage (65), so that characteristic polynomials of the input-output function are variable. The LFSR can fully or partly operate as a TYPE 1 or TYPE 2 LFSR which enables the execution of different algorithms on one hardware base.

Abstract: A memory device (50) contains a first array of memory (12) and a second array of memory (14). The arrays (12 and 14) are coupled to four segmented current data buses (iGDLs) (16, 18, 20, and 22). When in a x36 word mode of operation, the current data buses (16, 18, 20, and 22) are wired to communicate directly with output buffers (56-59) through several current-to-voltage converters (24-31). When in a x18 word mode of operation, the current data buses (16, 18, 20, and 22) are wired to communicate through the converts (24-31), through a voltage bus (52 and 54, see also FIG. 3), to the output buffers (56-59). The change in wiring for x36 word mode versus x18 word mode is done either by a top-level metal option in fabrication or by user software programming whereby the device (50) is easily wired into one of two configurations while maintaining an advantageous speed/power product.

Abstract: A method for polishing a metal layer (20) containing a combination of wide features (12), low density features (14), and high density features (18), is illustrated. A hydrophilic polish pad (24) having a shore D hardness of greater than 50 is used along with slurry (22) containing silica and an acidic based oxidizer such as oxadic acid in a chemical mechanical polishing (CMP) process. The result is less than 5:1 and preferably 1:1. This low selectivity results in the metal layer (20) being polished to a level below the surface of the surrounding oxide in a timed-controlled polish.

Abstract: A method for forming a trench transistor structure begins by forming a buried layers (12 and 16) and a doped well (22) in a substrate (10) via epitaxial growth processing. A trench region (24) is then etched into the substrate (10) to expose a the layer (12). A conductive sidewall spacer (28) is formed within the trench (24) as a gate electrode. The spacer (28) gates a first transistor (12, 28, 32) located adjacent a first half of the trench (24) and a second transistor (12, 28, 34) located adjacent a second half of the trench (24). Region (12) is a common electrode wherein the channel regions of both the first and second transistor are coupled in a serial manner through the region (12).

Abstract: A method for forming an interconnect structure on a semiconductor wafer (114) begins by placing the wafer (114) in a process chamber (100). The process chamber (100) contains a titanium (Ti) target (102) having a thin titanium nitride (TiN) layer (104) formed thereon. An argon-based plasma (106) is used to sputter the layer (104) off of the target (102) and onto a top surface of the water (114) to form an Argon Uniquely Sputtered Titanium Nitride (AUSTiN) layer (116) which has a nitrogen concentration gradient therethrough. After forming the layer (116), an argon-nitrogen plasma (107) is initiated to reform the titanium nitride (TiN) layer (104) on the target and complete the interconnect structure by forming a top stoichiometric or near stoichiometric titanium nitride layer (118) over the layer (116).