Chartered Semiconductor Manufacturing Ltd (corporation)

Globalfoundries Singapore Pte. Ltd.

Palanivel Balasubramaniam

Yelehanka Ramachandramurthy Pradeep

Elgin Kiok Quek

Jae Gon Lee

Chunshan Yin

Narayanan Balasubramanian

Arjun Kumar Kantimahanti

Subrahamanyam Chivukula

Madhusudan Mukhopdhyay

A device includes a substrate with a device region on which a transistor is formed. The device region includes active edge regions and an active center region which have different oxidation growth rates. A growth rate modifier (GRM) comprising dopants which modifies oxidation growth rate is employed to produce a gate oxide layer which has a uniform thickness. The GRM may enhance or retard the oxidation growth, depending on the type of dopants used. Fluorine dopants enhance oxidation growth rate while nitrogen dopants retard oxidation growth rate.

Modifying growth rate of a device layer

A method for forming a MOSFET having an LDD structure with minimal lateral dopant diffusion is described. A gate electrode is provided overlying a gate dielectric layer on a semiconductor substrate. Dielectric spacers are formed on sidewalls of the gate electrode. Source and drain regions are formed associated with the gate electrode. The gate electrode and source and drain regions are silicided. Thereafter, the spacers are removed to expose the semiconductor substrate. LDD regions are formed using plasma doping in the exposed semiconductor substrate between the source and drain regions and the gate electrode to complete formation of an LDD structure in the fabrication of an integrated circuit device.

Method for forming PLDD structure with minimized lateral dopant diffusion

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

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Singapore, Singapore

Palanivel Balasubramaniam