Agency for Science, Technology and Research

Chartered Semiconductor Manufacturing Ltd (corporation)

Institute of Microelectronics

Other

National University of Singapore

Agency for Sceince, Technology and Reasearch

Narayanan Balasubramanian

Ranganathan Nagarajan

Wei Yip Loh

Richard Hammond

Jun Cai

Yelehanka Ramachandramurthy Pradeep

Pang Dow Foo

Lakshmi Kanta Bera

Patrick Guo Qiang Lo

Jia Zhen Zheng

Rakesh Kumar

Navab Singh

Shajan Mathew

Ajay Agarwal

Byung Jin Cho

Palanivel Balasubramaniam

Yung Chii Liang

Chuck Jang

Arjun Kumar Kantimahanti

Chang Seo Park

Cai Jun

Ren Chang Hong

Palanivel Balasubramanian

Chivkula Subrahmanyam

Ieng Kin Lao

Yelehanka Ramachandamurthy Pradeep

Alan Cuthbertson

Patrick Guo Oiang Lo

Ching Win Kong

Balakumar Subramanian

A method of fabricating a sensor comprising a nanowire on a support substrate with a first semiconductor layer arranged on the support substrate is disclosed. The method comprises forming a fin structure from the first semiconductor layer, the fin structure comprising at least two supporting portions and a fin portion arranged there between; oxidizing at least the fin portion of the fin structure thereby forming the nanowire being surrounded by a first layer of oxide; and forming an insulating layer above the supporting portions; wherein the supporting portions and the first insulating layer form a microfluidic channel. A nanowire sensor is also disclosed. The nanowire sensor comprises a support substrate, a semiconducting fin structure arranged on the support substrate, the fin structure comprising at least two semiconducting supporting portions and a nanowire arranged there between; and a first insulating layer on a contact surface of the supporting portions; wherein the supporting portions and the first insulating layer form a microfluidic channel.

Nanowire sensor, nanowire sensor array and method of fabricating the same

A method is described to form a MOSFET with a fully silicided gate electrode and fully silicided, raised S/D elements that are nearly coplanar to allow a wider process margin when forming contacts to silicided regions. An insulator block layer is formed over STI regions and a conformal silicidation stop layer such as Ti/TiN is disposed on the insulator block layer and active region. A polysilicon layer is deposited on the silicidation stop layer and is planarized by a CMP process to form raised S/D elements. An oxide hardmask on the gate electrode is removed to produce a slight recess between the spacers. A silicidation process yields a gate electrode and raised S/D elements comprised of NiSi. Optionally, a recess is formed in the substrate between an insulator block mask and spacer and a Schottky barrier is used instead of a silicidation stop layer to form a Schottky Barrier MOSFET.

Fully salicided (FUCA) MOSFET structure

A process for forming both tensile and compressive strained silicon layers to accommodate channel regions of MOSFET or CMOS devices has been developed. After formation of shallow trench isolation structures as well as application of high temperature oxidation and activation procedures, the fabrication sequences used to obtain the strained silicon layers is initiated. A semiconductor alloy layer is deposited followed by an oxidation procedure used to segregate a germanium component from the overlying semiconductor alloy layer into an underlying single crystalline silicon body. The level of germanium segregated into the underlying single crystalline silicon body determines the level of strain, which is in tensile state of a subsequently selectively grown silicon layer. A second embodiment of this invention features the thinning of a portion of the semiconductor alloy layer prior to the oxidation procedure allowing a lower level of germanium to be segregated into a first underlying portion of the underlying single crystalline silicon body, while during the same oxidation procedure a second portion of the underlying single crystalline silicon body receives a higher level of germanium segregation. So the subsequently deposited silicon-germanium layer, although the same process and thickness, can be strained in different states (tensile or compressive) and levels, depending different underlying portions' germanium concentration.

Method of fabricating tensile strained layers and compressive strain layers for a CMOS device

A MOSFET device in strained silicon-on-SiGe and a method of forming the device are described. The said device achieves reduced junction leakage due to the lower band-gap values of SiGe. The method consists of forming isolation trenches in a composite strained-Si/SiGe substrate and growing a liner oxide by wet oxidation such that oxidation is selective to SiGe only, with negligible oxidation of silicon surfaces. Selective oxidation results in oxide encroachment under strained-Si, thereby reducing the junction area after device fabrication is completed. Reduced junction area leads to reduced n/p or p/n junction leakage current.

Method to reduce junction leakage current in strained silicon on silicon-germanium devices

A method of forming gate electrodes having different work functions includes forming a first well of a first conductivity type and a second well of a second conductivity type. Subsequently, a gate dielectric layer is deposited over the first and second wells. A multi-layer stack comprising two or more thin metal/metal nitride layers is next formed over the first well. A thick metal/metal nitride layer is formed over the multi-layer stack to form the first gate electrode. The thick metal/metal nitride layer is also formed over the gate dielectric layer portion extending over the second well, thereby forming the second gate electrode. The first and second electrodes are then annealed, and thereafter exhibit different work functions as desired.

Gate electrode architecture for improved work function tuning and method of manufacture

A method of constructing a dual metal gate CMOS structure that uses an ultra thin aluminum nitride (AIN) buffer layer between the metal gate and gate dielectric during processing for preventing the gate dielectric from being exposed in the metal etching process. After the unwanted gate metal is etched away, the CMOS structure is annealed. During the annealing, the buffer layer is completely consumed through reaction with the metal gate and a new metal alloy is formed, resulting in only a minimal increase in the equivalent oxide thickness. The buffer layer and gate metals play a key role in determining the work functions of the metal/dielectric interface, since the work functions of the original gate metals are modified as a result of the annealing process.

Method of fabricating a CMOS device with dual metal gate electrodes

Fully salicided (FUSA) MOSFET structure

A novel silicon RF LDMOSFET structure based on the use of a stacked LDD, is disclosed. The LDD has been modified from a single layer of N type material to a stack of three layers. These are upper and lower N type layers with a P type layer between them. The upper N type layer is heavily doped to reduce the on-resistance of the device, while the lower N type layer is lightly doped to reduce the output capacitance, thereby improving the high frequency performance. The middle P layer is heavily doped which allows it to bring about pinch-off of the two N layers, thereby raising the device's breakdown voltage. A process for manufacturing the device, as well as experimental data concerning its performance are also given.

Stacked LDD high frequency LDMOSFET

A process for manufacturing a buried oxide layer for use in partial SOI structures is described. The process begins with the etching of deep trenches into a silicon body. For a preselected depth below the surface, the inner walls of the trenches are protected and oxidation of said walls is then effected until pinch-off occurs, both inside the trenches and in the material between trenches. The result is a continuous layer of wade whose size and shape are determined by the number and location of the trenches. Application of the process to the manufacture of a partial SOI RFLDMOS structure is also described together with performance data for the resulting device.

Process for device using partial SOI

A structure and a process for manufacturing semiconductor devices with improved oxide coverage on the corners of a shallow trench isolation structure is described. The STI trench is etched using a pad oxide and silicon nitride layers as patterning elements. After trench etch, a thin conformal layer of either amorphous, epitaxial or polysilicon is deposited over the silicon nitride and within the trench and annealed. Where the silicon has been deposited on the silicon bottom and sides of the open trench, the annealing effectively forms a single crystal or epitaxial silicon. Next a silicon oxide liner is grown over the conformal silicon layer. The trench is then filled with silicon oxide, the structure is planarized by either chemical mechanical polishing or etching, and the nitride and pad oxide is removed This leaves a polysilicon film on the vertical edges of the filler oxide which extends slightly above the surface of the silicon substrate. A thermal oxidation step is performed converting the poly film into silicon oxide which slightly extends the STI field oxide into the active device region eliminating any reduced oxide coverage or oxide recesses in the corner regions.

Method of fabricating a shallow trench isolation structure with reduced local oxide recess near corner

A method of fabricating gate oxides of different thicknesses has been achieved. Active area isolations are provided in a silicon substrate to define low voltage sections and high voltage sections in the silicon substrate. A sacrificial oxide layer is formed overlying the silicon substrate. A silicon nitride layer is deposited overlying the sacrificial oxide layer. A masking oxide layer is deposited overlying the silicon nitride layer. The masking oxide layer is patterned to form a hard mask overlying the low voltage sections. The silicon nitride layer is etched through where exposed by the hard mask thereby exposing the sacrificial oxide layer overlying the high voltage section. The exposed sacrificial oxide layer and the hard mask are etched away. A thick gate oxide layer is grown overlying the silicon substrate in the high voltage section. The silicon nitride layer is etched away. The sacrificial oxide layer overlying the low voltage section is etched away. A thin gate oxide layer is grown overlying the silicon substrate in the low voltage section, and the integrated circuit device is completed.

Method to form gate oxides of different thicknesses on a silicon substrate

A method for forming gate structures with smooth sidewalls by amorphizing the polysilicon along the gate boundaries is described. This method results in minimal gate depletion effects and improved critical dimension control in the gates of smaller devices. The method involves providing a gate silicon oxide layer on the surface of the semiconductor substrate. A gate electrode layer, such as polysilicon is deposited over the gate silicon oxide followed by a masking oxide layer deposited over the gate electrode layer. The masking oxide layer is patterned for the formation of the gate electrode. An ion implantation of silicon or germanium amorphizes the area of the polysilicon not protected by the masking oxide mask and also amorphizes the area along the boundaries of the polysilicon gate. Thereafter, the amorphized silicon is then removed by an anisotropic etch leaving a narrow area of amorphized silicon on the gate electrode sidewalls under the edges of the masking oxide mask completing the gate structure having smooth sidewalls.

Method to form a smooth gate polysilicon sidewall in the fabrication of integrated circuits

A method for forming within an integrated circuit a low impurity diffusion polysilicon layer. Formed upon a semiconductor substrate is an amorphous silicon layer. Formed also upon the semiconductor substrate and contacting the amorphous silicon layer is a polysilicon layer. The amorphous silicon layer and the polysilicon layer are then simultaneously annealed to form a low impurity diffusion polysilicon layer. The low impurity diffusion polysilicon layer is a polysilicon multi-layer with grain boundary mis-matched polycrystalline properties. Optionally, a metal silicide layer may be formed upon the amorphous silicon layer and the polysilicon layer either prior to or subsequent to annealing the amorphous silicon layer and the polysilicon layer. The metal silicide layer and low impurity diffusion polysilicon layer may then be patterned to form a polycide gate electrode.

Method for forming a low impurity diffusion polysilicon layer

Growing community of inventors

Singapore, Singapore

Narayanan Balasubramanian