Proximity effect (electron beam lithography)

About: Proximity effect (electron beam lithography) is a research topic. Over the lifetime, 940 publications have been published within this topic receiving 8508 citations.

Formation of pattern

Abstract: PURPOSE: To relax the poor effect of a proximity effect between electron beam lithographies by executing an additional exposure by a beam flow current that is much larger than that used for exposure in a pattern region. CONSTITUTION: An additional charge is injected into adjacent regions 2-2 and 2-4. While a grating is manufactured, a line in a first region 2-2 is written by a duty cycle of, for example, 1:1. The region has a width b1 of 5 μm. A charge is injected in the adjacent regions 2-4 and 2-6 (with a width b2 of 10 μm). Charge is injected uniformly or is charged by another arbitrary method as far as the charge is distributed nearly uniformly within the adjacent regions 2-4 and 2-6. In the latter case, a beam diameter (and hence the beam current of an electron source with a constant brightness) is increased drastically.

Absence of magnetic interactions in Ni–Nb ferromagnet–superconductor bilayers

Abstract: Studies of ferromagnet-superconductor hybrid systems have uncovered magnetic interactions between the competing electronic orderings. The electromagnetic (EM) proximity effect predicts the formation of a spontaneous vector potential inside a superconductor placed in proximity to a ferromagnet. In this work, we use a Nb superconducting layer and Ni ferromagnetic layer to test for such magnetic interactions. We use the complementary, but independent, techniques of polarized neutron reflectometry and detection Josephson junctions to probe the magnetic response inside the superconducting layer at close to zero applied field. In this condition, Meissner screening is negligible, so our measurements examine only additional magnetic and screening contributions from proximity effects. We report the absence of any signals originating from EM proximity effect in zero applied field. Our observations indicate that either EM proximity effect is below the detection resolution of both of our experiments or may indicate a new phenomenon that requires extension of current theory. From our measurements, we estimate a limit of the size of the zero field EM proximity effect in our Ni–Nb samples to be ±0.27 mT.

An E-beam direct write process for 16M-Bit DRAMs

Abstract: For obtaining a very fine wafer pattern below half micron, direct write EB lithography has charging and proximity effect problems. A method of compensating for the charging problem is to use a 40 kV proton shower irradiation process which decreases the bottom layer resistance of the trilayer resist. The charge of the electron beam is dissipated through the bottom-layer resist. As for the proximity effect, we developed a proximity effect correction software system by dosage modification. The theoretical and experimental results showed that in a 2.2-micron-thick trilayer planarizing resist system, a 0.5-micron isolated line, 0.5-micron isolated space, and 0.5-micron contact holes were simultaneously resolved in a half-micron-thick top-layer resist. The resultant half-micron-rule 16M-bit DRAM patterns were successfully obtained on uneven topography of the processed wafer using EB direct write.

Mask data generating method, mask manufacturing method and method of manufacturing semiconductor device

Abstract: PROBLEM TO BE SOLVED: To provide a mask data generating method for easily confirming whether an optical proximity effect correction pattern is automatically generated or not in the prescribed part of an arbitrary layer. SOLUTION: The method has a step (a) for setting a correction pattern generation area for automatically generating a correction pattern for correcting optical proximity effect to a pattern having the width of not more than a prescribed value, a step (b) for setting a correction pattern inhibition area for inhibiting the automatic generation of the correction pattern, a step (c) for inputting data on a correction confirming pattern having the width of not more than the prescribed value in the correction pattern generation area and the inhibition area, a step (d) for inputting data on the pattern for forming the layer of a semiconductor device and a step (e) for automatically generating the correction pattern.

Method for forming an auxiliary pattern in a mask for a semiconductor device and a mask for a semiconductor device manufactured by using the method

Abstract: PURPOSE: A method for forming an auxiliary pattern in a mask for a semiconductor device and a mask for a semiconductor device manufactured by using the method are provided to form a desired pattern finely after an exposure process by forming an auxiliary pattern for compensating an optical proximity effect CONSTITUTION: In a device, a separation distance between main patterns(1) is checked A central line is perpendicularly formed at a part which is the separation distance over the checked separation distance The distance to an adjacent main pattern is checked from each central line First assistant patterns(160,170,180) are formed at the central line of a disk The first assistant pattern is arranged between the main patterns having the separation distance over a predetermined level Second subsidiary patterns(230,240) are arranged between the main patterns adjacent to the first assistant pattern