Different sized features in the array and in the periphery of an integrated circuit are patterned on a substrate in a single step. In particular, a mixed pattern, combining two separately formed patterns, is formed on a single mask layer and then transferred to the underlying substrate. The first of the separately formed patterns is formed by pitch multiplication and the second of the separately formed patterns is formed by conventional photolithography. The first of the separately formed patterns includes lines that are below the resolution of the photolithographic process used to form the second of the separately formed patterns. These lines are made by forming a pattern on photoresist and then etching that pattern into an amorphous carbon layer. Sidewall pacers having widths less than the widths of the un-etched parts of the amorphous carbon are formed on the sidewalls of the amorphous carbon. The amorphous carbon is then removed, leaving behind the sidewall spacers as a mask pattern. Thus, the spacers form a mask having feature sizes less than the resolution of the photolithography process used to form the pattern on the photoresist. A protective material is deposited around the spacers. The spacers are further protected using a hard mask and then photoresist is formed and patterned over the hard mask. The photoresist pattern is transferred through the hard mask to the protective material. The pattern made out by the spacers and the temporary material is then transferred to an underlying amorphous carbon hard mask layer. The pattern, having features of difference sizes, is then transferred to the underlying substrate.

Method for integrated circuit fabrication using pitch multiplication

Single spacer processes for multiplying pitch by a factor greater than two are provided. In one embodiment, n, where n≧2, tiers of stacked mandrels are formed over a substrate, each of the n tiers comprising a plurality of mandrels substantially parallel to one another. Mandrels at tier n are over and parallel to mandrels at tier n−1, and the distance between adjoining mandrels at tier n is greater than the distance between adjoining mandrels at tier n−1. Spacers are simultaneously formed on sidewalls of the mandrels. Exposed portions of the mandrels are etched away and a pattern of lines defined by the spacers is transferred to the substrate.

Single spacer process for multiplying pitch by a factor greater than two and related intermediate IC structures

Differently-sized features of an integrated circuit are formed by etching a substrate using a mask which is formed by combining two separately formed patterns. Pitch multiplication is used to form the relatively small features of the first pattern and conventional photolithography used to form the relatively large features of the second pattern. Pitch multiplication is accomplished by patterning a photoresist and then etching that pattern into an amorphous carbon layer. Sidewall spacers are then formed on the sidewalls of the amorphous carbon. The amorphous carbon is removed, leaving behind the sidewall spacers, which define the first mask pattern. A bottom anti-reflective coating (BARC) is then deposited around the spacers to form a planar surface and a photoresist layer is formed over the BARC. The photoresist is next patterned by conventional photolithography to form the second pattern, which is then is transferred to the BARC. The combined pattern made out by the first pattern and the second pattern is transferred to an underlying amorphous silicon layer and the pattern is subjected to a carbon strip to remove BARC and photoresist material. The combined pattern is then transferred to the silicon oxide layer and then to an amorphous carbon mask layer. The combined mask pattern, having features of difference sizes, is then etched into the underlying substrate through the amorphous carbon hard mask layer.

Pitch reduced patterns relative to photolithography features

The dimensions of mask patterns, such as pitch-multiplied spacers, are controlled by controlled growth of features in the patterns after they are formed. To form a pattern of pitch-multiplied spacers, a pattern of mandrels is first formed overlying a semiconductor substrate. Spacers are then formed on sidewalls of the mandrels by depositing a blanket layer of material over the mandrels and preferentially removing spacer material from horizontal surfaces. The mandrels are then selectively removed, leaving behind a pattern of freestanding spacers. The spacers comprise a material, such as polysilicon and amorphous silicon, known to increase in size upon being oxidized. The spacers are oxidized to grow them to a desired width. After reaching the desired width, the spacers can be used as a mask to pattern underlying layers and the substrate. Advantageously, because the spacers are grown by oxidation, thinner blanket layers can be deposited over the mandrels, thereby allowing the deposition of more conformal blanket layers and widening the process window for spacer formation.

Mask material conversion

After forming a resist film including a hygroscopic compound, pattern exposure is performed by selectively irradiating the resist film with exposing light while supplying water onto the resist film. After the pattern exposure, the resist film is developed so as to form a resist pattern.

Pattern formation method

A method and system of making a mask with a transparent substrate thereon is provided. A first resolution enhancement structure is formed on the first portion of the transparent substrate. A second resolution enhancement structure is formed on a second portion of the transparent substrate, with the second resolution enhancement structure different from the first resolution enhancement structure.

Semiconductor manufacturing resolution enhancement system and method for simultaneously patterning different feature types

An exemplary method of forming integrated circuit device features by oxidization of titanium hard mask is described. This method can include providing a photoresist pattern of photoresist features over a first layer of material deposited over a second layer of material; etching the first layer of material according to the photoresist pattern to form material features; oxidizing exposed portions of the material features where the material features are made of a material which expands during oxidation; and etching the second layer of material according to the material features which have expanded as a result of oxidation. Advantageously, the expansion of the material features results in a smaller distance between material features than the distance between photoresist features.

Method of forming integrated circuit features by oxidation of titanium hard mask

The present invention generally relates to a method of forming a graded junction within a semiconductor substrate. A first masking pattern having a first opening characterized by a first lateral dimension is formed over the semiconductor substrate. The semiconductor substrate is doped with a first dopant, using the first masking pattern as a doping mask, thereby forming a first dopant region in the semiconductor substrate underlying the first opening. The first masking pattern is swelled to decrease the first lateral dimension of the first opening to a second lateral dimension. The semiconductor substrate is then doped with a second dopant, using the swelled first masking pattern as a doping mask, thereby forming a second dopant region in the semiconductor substrate, and furthermore defining a graded junction within the semiconductor substrate.

RELACS shrink method applied for single print resist mask for LDD or buried bitline implants using chemically amplified DUV type photoresist

A method of manufacturing for a MirrorBit® Flash memory includes depositing a charge-trapping material over a semiconductor substrate and implanting first and second bitlines in the semiconductor substrate A wordline material is deposited over the charge-trapping dielectric material and a hard mask material deposited thereon An anti-reflective coating (ARC) material is deposited on the hard mask material and a photoresist material is deposited on the ARC followed by processing the photoresist material and the ARC material to form a photomask of a patterned photoresist and a patterned ARC The hard mask material is processed using the photomask to form a hard mask The patterned photoresist is removed and then the patterned ARC without damaging the hard mask or the wordline material The wordline material is processed using the hard mask to form a wordline and the hard mask is removed without damaging the wordline or the charge-trapping material

Flash memory with controlled wordline width

A method of removing organic anti-reflective coating (ARC) by ashing in an integrated circuit fabrication process can include providing an oxide-nitride-oxide (ONO) stack over a silicon substrate, providing a poly layer over the ONO stack, and patterning spaces in the poly layer using a patterned carbon bilayer ARC layer and a patterned hardmask layer. The patterned carbon bilayer ARC layer is ashed away before patterning spaces in the poly layer. Ashing the carbon bilayer ARC layer helps prevent damage to the ONO stack, improving the quality of the fabricated device.

Kouros Ghandehari

Papers

Semiconductor manufacturing resolution enhancement system and method for simultaneously patterning different feature types

Method of forming integrated circuit features by oxidation of titanium hard mask

RELACS shrink method applied for single print resist mask for LDD or buried bitline implants using chemically amplified DUV type photoresist

Flash memory with controlled wordline width

Application of the CVD bilayer ARC as a hard mask for definition of the subresolution trench features between polysilicon wordlines