Abstract: A shallow trench isolation is disclosed wherein the trench depth is reduced beyond that achieved in prior art processes. The reduced trench depth helps to eliminate the formation of voids during the trench refill process and provides for greater planarity in the final isolation structure. Effective device isolation is achieved with a reduced trench depth by utilizing refilling dielectric materials having low dielectric constant.

Abstract: Thin film metal-insulator-metal capacitors having enhanced surface area are formed by a substituting metal for silicon in a preformed electrode geometry. The resulting metal structures are advantageous for high-density DRAM applications since they have good conductivity, enhanced surface area and are compatible with capacitor dielectric materials having high dielectric constant.

Abstract: According to an exemplary method in one embodiment, a transistor gate is fabricated on a substrate. Next, an etch stop layer may be deposited on the substrate. The etch stop layer may, for example, be TEOS silicon dioxide. Thereafter, a conformal layer is deposited over the substrate and the transistor gate. The conformal layer may, for example, be silicon nitride. An opening is then etched in the conformal layer. Next, a base layer is deposited on the conformal layer and in the opening. The base layer may, for example, be silicon-germanium. According to this exemplary embodiment, an emitter may be formed on the base layer in the opening. Next, the base layer is removed from the conformal layer. The conformal layer is then etched back to form a spacer adjacent to the transistor gate. In one embodiment, a structure is fabricated according to the above described exemplary method.

Abstract: The invention provides semiconductor processing methods of depositing SiO2 on a substrate. In a preferred aspect, the invention provides methods of reducing the formation of undesired reaction intermediates in a chemical vapor deposition (CVD) decomposition reaction. In one implementation, the method is performed by feeding at least one of H2O and H2O2 into a reactor with an organic silicon precursor. For example, in one exemplary implementation, such components are, in gaseous form, fed separately into the reactor. In another exemplary implementation, such components are combined in liquid form prior to introduction into the reactor, and thereafter rendered into a gaseous form for provision into the reactor. The invention can be practiced with or in both hot wall and cold wall CVD systems.

Abstract: One embodiment is a method for fabricating the base of a bipolar transistor where the method comprises placing a first wafer in an undoped epi chamber. Next a first undoped base layer is grown over the first wafer. After growing the first undoped base layer, the first wafer is transferred from the undoped epi chamber into a separate doped epi chamber. A first doped base layer is then grown over the first undoped based layer in the doped epi chamber. While the first wafer is being processed in the doped epi chamber, a second wafer can be processed in the undoped epi chamber. Another embodiment is a structure produced by the disclosed method and yet another embodiment comprises a transfer chamber, a transfer arm, a bake chamber, and a separate undoped epi chamber and a doped epi chamber for practicing the disclosed method.

Abstract: According to a disclosed embodiment, an etch stop layer is fabricated on top of a base. An amorphous layer is then formed on top of the etch stop layer. An opening is then etched in the amorphous layer and the etch stop layer. The opening is etched with an opening width substantially equal to a critical dimension. The opening with opening width substantially equal to a critical dimension is then filled with a polycrystalline emitter. The resulting polycrystalline emitter has an emitter width substantially equal to the critical dimension. Moreover, a polycrystalline emitter structure can be fabricated, in which the critical dimension, i.e. the emitter width, is precisely controlled. The result is a polycrystalline emitter structure which is substantially as small as the resolution that the photolithography process would allow.

Abstract: A shallow trench isolation is disclosed wherein the trench depth is reduced beyond that achieved in prior art processes. The reduced trench depth helps to eliminate the formation of voids during the trench refill process and provides for greater planarity in the final isolation structure. Effective device isolation is achieved with a reduced trench depth by utilizing refilling dielectric materials having low dielectric constant.

Abstract: According to an exemplary method in one embodiment, a transistor gate is fabricated on a substrate. Next, an etch stop layer may be deposited on the substrate. The etch stop layer may, for example, be TEOS silicon dioxide. Thereafter, a conformal layer is deposited over the substrate and the transistor gate. The conformal layer may, for example, be silicon nitride. An opening is then etched in the conformal layer. Next, a base layer is deposited on the conformal layer and in the opening. The base layer may, for example, be silicon-germanium. According to this exemplary embodiment, an emitter may be formed on the base layer in the opening. Next, the base layer is removed from the conformal layer. The conformal layer is then etched back to form a spacer adjacent to the transistor gate. In one embodiment, a structure is fabricated according to the above described exemplary method.

Abstract: One embodiment is a method for fabricating the base of a bipolar transistor where the method comprises placing a first wafer in an undoped epi chamber. Next a first undoped base layer is grown over the first wafer. After growing the first undoped base layer, the first wafer is transferred from the undoped epi chamber into a separate doped epi chamber. A first doped base layer is then grown over the first undoped based layer in the doped epi chamber. While the first wafer is being processed in the doped epi chamber, a second wafer can be processed in the undoped epi chamber. Another embodiment is a structure produced by the disclosed method and yet another embodiment comprises a transfer chamber, a transfer arm, a bake chamber, and a separate undoped epi chamber and a doped epi chamber for practicing the disclosed method.

Abstract: According to one exemplary embodiment, a heterojunction bipolar transistor comprises a base. The heterojunction bipolar transistor further comprises a first nitride spacer and a second nitride spacer situated on the base, where the first nitride spacer and the second nitride spacer are separated by a distance substantially equal to a critical dimension. For example, the first nitride spacer and the second nitride spacer may comprise LPCVD or RTCVD silicon nitride. According to this exemplary embodiment, the heterojunction bipolar transistor further comprises an emitter situated between said first nitride spacer and said second nitride spacer, where the emitter has a width substantially equal to the critical dimension. The emitter may, for example, comprise polycrystalline silicon. In another embodiment, a method that achieves the above-described heterojunction bipolar transistor is disclosed.

Abstract: According to one exemplary embodiment, a method for fabricating a bipolar transistor, such as a heterojunction bipolar transistor (“HBT”), comprises fabricating a first inner spacer and a second inner spacer on a top surface of a base. The method further comprises forming a first outer spacer adjacent to the first inner spacer and a second outer spacer adjacent to the second inner spacer. According to this exemplary embodiment, the method further comprises depositing an emitter between the first and second inner spacers on the top surface of the base. The method may further comprise depositing an intermediate oxide layer on the first and second outer spacers after forming the first and second outer spacers. The method may further comprise depositing an amorphous layer on the intermediate oxide layer. The method may also comprise depositing an antireflective coating layer on the amorphous layer.

Abstract: According to a disclosed embodiment, a gas is supplied at a certain partial pressure for a chemical reaction with a top surface of a base in a transistor. The top surface of the base is heated to a certain temperature to promote the chemical reaction. For example, the gas can be oxygen, the base can be an epitaxial single crystal silicon-germanium base of a heterojunction bipolar transistor (“HBT”), and the chemical reaction can be oxidation of the silicon in the top surface of the silicon-germanium base. In one embodiment of the invention, the partial pressure of oxygen is maintained at 0.1 atmosphere and the top surface of the base is heated using rapid thermal processing (“RTP”) to a temperature of 500° C. The chemical reaction forms a dielectric layer on the top surface of the base. For example, using oxygen as stated above, a dielectric layer of silicon oxide (“interfacial oxide”) is formed.

Abstract: According to one exemplary embodiment, a heterojunction bipolar transistor is fabricated by forming a metastable epitaxial silicon-germaniuim base on a collector. The metastable epitaxial silicon-germanium base, for example, may have a concentration of germanium greater than 20.0 atomic percent of germanium. The heterojunction bipolar transistor, for example, may be an NPN silicon-germanium heterojunction bipolar transistor. According to this exemplary embodiment, the heterojunction bipolar transistor is further fabricated by fabricating an emitter over the metastable epitaxial silicon-germanium base. The heterojunction bipolar transistor is further fabricated by doping the emitter with a first dopant. The first dopant, for example, may be arsenic.

Abstract: According to a disclosed embodiment, a base region is grown on a transistor region. A dielectric layer is next deposited over the base region. The dielectric layer can comprise, for example, silicon dioxide, silicon nitride, or a suitable low-k dielectric. Subsequently, an opening is fabricated in the dielectric layer, and an emitter layer is formed on top of the dielectric layer and in the opening. Thereafter, an anisotropic polymerizing etch chemistry is utilized to etch the emitter layer down to a first depth, forming an emitter region in the opening. Next, a non-polymerizing etch chemistry having isotropic components is used to create a notch in the dielectric layer below the emitter region. The formation of the notch reduces the overlap area of a capacitor that forms between the emitter region and the base region, which translates to a lower level of emitter to base capacitance.

Abstract: According to one exemplary embodiment, a heterojunction bipolar transistor comprises a base having a top surface. The heterojunction bipolar transistor further comprises a first spacer and a second spacer situated on the top surface of the base. The heterojunction bipolar transistor further comprises an intermediate oxide layer situated on the first and second oxide spacers. The heterojunction bipolar transistor further comprises an amorphous layer situated on the intermediate oxide layer. The heterojunction bipolar transistor further comprises an antireflective coating layer on the amorphous layer. The heterojunction bipolar transistor further comprises an emitter window opening situated between the first and second spacers, where the emitter window opening is defined by the top surface of the base, the first and second spacers, the intermediate oxide layer, the amorphous layer, and the antireflective coating layer.

Abstract: According to one exemplary embodiment, a heterojunction bipolar transistor comprises a base having a top surface. The heterojunction bipolar transistor further comprises a first spacer and a second spacer situated on the top surface of the base. The heterojunction bipolar transistor further comprises an intermediate oxide layer situated on the first and second oxide spacers. The heterojunction bipolar transistor further comprises an amorphous layer situated on the intermediate oxide layer. The heterojunction bipolar transistor further comprises an antireflective coating layer on the amorphous layer. The heterojunction bipolar transistor further comprises an emitter window opening situated between the first and second spacers, where the emitter window opening is defined by the top surface of the base, the first and second spacers, the intermediate oxide layer, the amorphous layer, and the antireflective coating layer.

Abstract: According to one exemplary embodiment, a heterojunction bipolar transistor comprises a base having a concentration of a first material at a first depth, where the first material impedes the diffusion of a base dopant. The first material also causes a change in band gap at the first depth in the base. According to this exemplary embodiment, the base further includes a concentration of a second material, where the concentration of second material increases at the first depth so as to counteract the change in band gap.

Abstract: According to one disclosed embodiment, a transistor gate is fabricated on a substrate. For example, the gate can be a polycrystalline silicon gate in a FET. Thereafter, a conformal layer is deposited over the substrate and the gate and is then etched back to form spacers on the sides of the gate. An underlying dielectric layer is formed on the substrate, gate, and spacers. The conformal layer and the underlying dielectric layer can be comprised of, for example, a dielectric such as silicon dioxide, silicon nitride, or a low-k dielectric. Next, an overcoat layer is fabricated on the underlying dielectric layer. The overcoat layer can be, for example, polycrystalline silicon. Following, an opening is etched in the overcoat layer and the underlying dielectric layer wherein subsequent films can be grown. For example, silicon germanium can be grown in the opening for fabrication of a silicon germanium heterojunction bipolar transistor.

Abstract: According to one exemplary embodiment, a bipolar transistor, such as a heterojunction bipolar transistor (“HBT”), comprises a base having a top surface. The HBT further comprises a first inner spacer and a second inner spacer situated on the top surface of the base. The HBT further comprises a first outer spacer situated adjacent to the first inner spacer and a second outer spacer situated adjacent to the second inner spacer on the top surface of the base. According to this exemplary embodiment, the HBT further comprises an emitter situated between the first and second inner spacers. The HBT may further comprise an intermediate oxide layer situated on the first and second outer spacers. The HBT may further comprise an amorphous layer situated on said intermediate oxide layer. The HBT may also comprise an antireflective coating layer on the amorphous layer.

Abstract: According to one exemplary embodiment, a heterojunction bipolar transistor comprises a base having a top surface. The heterojunction bipolar transistor further comprises an epitaxial emitter selectively situated on the top surface of the base. For example, the epitaxial emitter may be N-type single-crystal silicon. The heterojunction bipolar transistor further comprises an etch stop layer situated on the top surface of the base, where the etch stop layer is in contact with the epitaxial emitter. The heterojunction bipolar transistor further comprises a first spacer and a second spacer situated on the etch stop layer, where the epitaxial emitter is situated between the first and second spacer. The first spacer and the second spacer, for example, may be LPCVD silicon nitride. The heterojunction bipolar transistor further comprises a dielectric layer deposited on the first and second spacers.