摘要:
A method is disclosed for fabricating monocrystal material with the bandgap width exceeding 1.8 eV. The method comprises the steps of processing a monocrystal semiconductor wafer to develop a porous layer through electrolytic treatment of the wafer at direct current under UV-illumination, and epitaxially growing a monocrystal layer on said porous layer. Growth on porous layer produces semiconductor material with reduced stress and better characteristics than with the same material grown on non-porous layers and substrates. Also, semiconductor device structure comprising at least one layer of porous group III material is included.
摘要:
The invention relates to a method for locally deforming an optical element for photolithography in accordance with a predefined deformation form comprising: (a) generating at least one laser pulse having at least one laser beam parameter; and (b) directing the at least one laser pulse onto the optical element, wherein the at least one laser beam parameter of the laser pulse is selected to yield the predefined deformation form.
摘要:
A method for correcting a plurality of errors of a photolithographic mask, comprising optimizing first parameters of a imaging transformation of the photolithographic mask and second parameters of a laser beam locally directed onto the photolithographic mask, and correcting the plurality of errors by applying an imaging transformation using optimized first parameters and locally directing the laser beam onto the photolithographic mask using optimized second parameters, wherein the first and the second parameters are simultaneously optimized in a joint optimization process.
摘要:
In general, in one aspect, a method includes determining a critical dimension (CD) distribution on a photomask by measuring deep Ultra-Violet (DUV) transmission across the photomask.
摘要:
There is disclosed herein an apparatus for electromagnetic forming of a workpiece with enhancements that increase the durability and overall efficiency of the solenoid coil. The apparatus includes reinforcement members dispersed through the solenoid coil and a cooling system. The apparatus also includes a shaper that varies in girth effectively acting as a force concentrator. The electromagnetic forming device is also capable of incrementally heat treating the workpiece and reducing residual stresses in the workpiece. The invention further discloses a more efficient way of manufacturing the solenoid coil.
摘要:
A method for growing bulk GaN and AlGaN single crystal boules, preferably using a modified HVPE process, is provided. The single crystal boules typically have a volume in excess of 4 cubic centimeters with a minimum dimension of approximately 1 centimeter. If desired, the bulk material can be doped during growth to achieve n-, i-, or p-type conductivity. In order to have growth cycles of sufficient duration, preferably an extended Ga source is used in which a portion of the Ga source is maintained at a relatively high temperature while most of the Ga source is maintained at a temperature close to, and just above, the melting temperature of Ga. To grow large boules of AlGaN, preferably multiple Al sources are used, the Al sources being sequentially activated to avoid Al source depletion and excessive degradation. In order to achieve high growth rates, preferably a dual growth zone reactor is used in which a first, high temperature zone is used for crystal nucleation and a second, low temperature zone is used for rapid crystal growth. Although the process can be used to grow crystals in which the as-grown material and the seed crystal are of different composition, preferably the two crystalline structures have the same composition, thus yielding improved crystal quality.
摘要:
Bulk GaN and AlGaN single crystal boules, preferably fabricated using a modified HVPE process, are provided. The single crystal boules typically have a volume in excess of 4 cubic centimeters with a minimum dimension of approximately 1 centimeter. If desired, the bulk material can be doped during growth, for example to achieve n-, i-, or p-type conductivity.
摘要:
A transition crystal structure is disclosed for providing a good lattice and thermal match between a layer of single crystal silicon carbide and a layer of single crystal gallium nitride. The transition structure comprises a buffer formed of a first layer of gallium nitride and aluminum nitride, and a second layer of gallium nitride and aluminum nitride adjacent to the first layer. The mole percentage of aluminum nitride in the second layer is substantially different from the mole percentage of aluminum nitride in the first layer. A layer of single crystal gallium nitride is formed upon the second layer of gallium nitride. In preferred embodiments, the buffer further comprises an epitaxial layer of aluminum nitride upon a silicon carbide substrate.
摘要:
The invention relates to a method for correcting at least one error on wafers processed by at least one photolithographic mask, the method comprises: (a) measuring the at least one error on a wafer at a wafer processing site, and (b) modifying the at least one photolithographic mask by introducing at least one arrangement of local persistent modifications in the at least one photolithographic mask.
摘要:
A contribution to a wafer level critical dimension distribution from a scanner of a lithography system can be determined based on measured wafer level critical dimension uniformity distribution and a contribution to the wafer level critical dimension distribution from a photo mask. Light transmission (104) across the photo mask (162) can be measured, a transmittance variation distribution of the photo mask can be determined, and the contribution to the wafer level critical dimension distribution from the photo mask (162) can be determined (132) based on the transmittance variation distribution of the photo mask.