Abstract: An IQ mixer and a method thereof. The IQ mixer comprises a pair of Gilbert cells and a degeneration inductor. Each pair of Gilbert cells comprises a pair of first current generators and a pair of switching networks. The pair of first current generators converts an RF signal pair to currents respectively. The pair of switching networks, coupled to the first current generator, modulates the converted RF signal pair with an oscillation signal pair to generate a mixed signal pair. The degeneration inductor is coupled to all pairs of the first current generators, such that it is shared by the pair of Gilbert cells.

Abstract: Calibration methods and circuits for suppressing second order distortion in a direct conversion receiver. In the calibration method, a signal output by a down converter is filtered to obtain an interference signal, and strength of the interference signal is detected. A calibration code is obtained according to the detected strength of the interference signal, and the down converter is adapted according to the calibration code to suppress second order distortion.

Abstract: A method for forming a patterned microelectronics layer employing electron beam lithography in a sensitive material upon a substrate with optimal correction for proximity effects resulting from electron back scattering into the resist material. There is provided a substrate having formed thereon a layer of resist material sensitive to electron beam exposure. There is then exposed the sensitive layer to a vector scan shaped electron beam to write a primary pattern with dose correction of the beam dose for proximity effects due to electron scattering at each point in the primary pattern. There is then written a secondary pattern which is a negative reversed image of the primary pattern in a secondary exposure employing a vector scan shaped focused electron beam at an exposure dose substantially below the primary beam dose, there being provided a gap between the primary pattern and the secondary pattern.

Abstract: A method for forming a patterned microelectronics layer employing electron beam lithography in a sensitive material upon a substrate with optimal correction for proximity effects resulting from electron back scattering into the resist material. There is provided a substrate having formed thereon a layer of resist material sensitive to electron beam exposure. There is then exposed the sensitive layer to a vector scan shaped electron beam to write a primary pattern with dose correction of the beam dose for proximity effects due to electron scattering at each point in the primary pattern There is then written a secondary pattern which is a negative reversed image of the primary pattern in a secondary exposure employing a vector scan shaped focused electron beam at an exposure dose substantially below the primary beam dose, there being provided a gap between the primary pattern and the secondary pattern.

Abstract: A method of fabricating an attenuating phase-shifting photomask, comprising the following steps. A photomask blank is provided having an upper resist layer overlying a chromium layer, the chromium layer overlying a phase-shifting layer, and the phase-shifting layer over a substrate. The photomask blank having a low pattern density area with a pattern density less than 0.25, a middle pattern density area with a pattern density from about 0.25 to 0.70, and a high pattern density area with a pattern density between about 0.70 and 1.00. The photomask blank is exposed to a first E-beam energy in a single step wherein the low pattern density area is exposed to the first E-beam energy adjusted by a first dosage factor, the middle pattern density area is exposed to the first E-beam energy adjusted by a second dosage factor, and the high pattern density area is exposed to the first E-beam energy adjusted by a third dosage factor.

Abstract: A method of fabricating an attenuating phase-shifting photomask, comprising the following steps. A photomask blank is provided having an upper resist layer overlying a chromium layer, the chromium layer overlying a phase-shifting layer, and the phase-shifting layer over a substrate. The photomask blank having a low pattern density area with a pattern density less than 0.25, a middle pattern density area with a pattern density from about 0.25 to 0.70, and a high pattern density area with a pattern density between about 0.70 and 1.00. The photomask blank is exposed to a first E-beam energy in a single step wherein the low pattern density area is exposed to the first E-beam energy adjusted by a first dosage factor, the middle pattern density area is exposed to the first E-beam energy adjusted by a second dosage factor, and the high pattern density area is exposed to the first E-beam energy adjusted by a third dosage factor.

Abstract: A method for repairing shifter layer defects in a phase shifting mask. A two step process is used to form an equivalent shifter layer with about the same light transmittance and phase angle shift as an original, non-defective shifter layer. (Typically for a DUV APSM, transmittance is about 6% and phase angle shift is about 180 degrees.) The first step is to etch the quartz substrate in a focus ion beam repair machine, using XeF2 gas, to cause a leading phase angle shift. The second step is to deposit an equivalent shifter layer in-situ in the focus ion beam repair machine, using a carbon based gas. When the equivalent shifter layer has about the same transmittance as the original shifter layer (e.g. 6%), the phase angle is lagging less than 180 degrees. The leading phase angle shift caused by etching the quartz substrate and the lagging phase angle caused by the equivalent shifter layer combine to produce a phase angle 180 degrees leading.

Abstract: A method for modulating the phase angle of a phase shift mask employed in deep ultraviolet (DUV) photolithography. There is provided a quartz substrate within which may be formed an engraved pattern, and upon which is formed a patterned phase shift layer. The phase angle of the phase shift layer upon the quartz substrate may be incrementally increased or decreased by subtractive etching of the phase shift layer and quartz substrate of the phase shift mask in an alkaline solution at a selected temperature and concentration for a period of time.

Abstract: A mask combining an alternating phase shift part and an attenuating phase shift part on a single blank and a method of forming said mask. The method involves fewer processing steps, fewer layers of material and is more cost effective than other methods in the current art. A central reason for the simplicity of the method is the use of different intensity levels of E-beam exposure in a single resist layer and achieving phase shifts by transmitting radiation through alternating regions of the same transparent substrate that are etched and not etched.

Abstract: A method is disclosed for employing direct electron beam writing in the lithography used for forming step-profiles in semiconductor devices. The number of steps in the profiles are not limited. An electron beam sensitive resist is formed over a substrate. The resist is then exposed to a scanning electron beam having precise information, including proximity effect correction data, to directly form stair-case-like openings in the resist. The highly accurately dimensioned step-profiles are then transferred into the underlying layers by performing appropriate etchings. The resulting structures are shown to be especially suitable for forming damascene interconnects for submicron technologies.