The dry etch resistance of metal‐free organic materials, mainly resist materials, has been studied. Etch rates have been measured under argon ion‐beam, oxygen ion‐beam, and oxygen plasma etching conditions. It is found that the etch rate under ion bombardment has a linear dependence on the “N/false(Nnormalc−Nnormalofalse)normalfactor” of the etched materials, where N , Nc , and N0 denote the total number of atoms in a monomer unit, the number of carbon atoms in a monomer unit, and the number of oxygen atoms in a monomer unit, respectively. The results indicate that the dry etch resistance under ion bombardment is determined by the effective carbon content in a material. The etch rates of the polymers in an oxygen plasma condition have no simple correlation with the effective carbon content in a material. This implies that etching mechanism under ion bombardment differs from the etching mechanism by radical species.

A nonpolymer material, calixarene derivative (hexaacetate p-methnylcalix[6]arene) was tested as a high-resolution negative resist under an electron beam lithography process. It showed under 10-mm resolution with little side roughness and high durability to halide plasma etching. A sub-10-nm Ge quantum wire was perfectly etched off without defects. Such a performance is suitable for nanoscale device processes.

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New electron beam (EB) resists made of calixarene resists are introduced. Typical sensitivities of calixarene resists range from 700 µ C/cm2 to 7 mC/cm2. High-density dot arrays with 15 nm diameter constructed using calixarene resist were easily delineated using a point EB lithography system. Our results suggest that the resolution limit of calixarene resists is dominated by a development process such as adhesion to a substrate rather than by the EB profile. Calixarene resists are resistant to etching by halide plasma. We also demonstrated nanoscale devices processed by using calixarene resists. Calixarene resists are promising materials for nanofabrication.

The microwave spectrum of cyclohexanone has been investigated in the frequency region from 7.7 to 23.4 Gc/sec. The R- and Q-branches for both the a- and the c-type have been assigned for the vibrationally ground state. The rotational constants obtained are A=4195.30 Mc/ sec, B=2502.57 Mc/sec, and C=1754.49 Mc/sec. From these values it can be concluded that the molecules have the chair form. The value of the component of the dipole moment |μa| is 2.74±0.03 D, and that of |μc| is 0.86±0.03 D. The value of the total dipole moment is 2.87±0.04 D, a value which is in agreement with that obtained by Debye’s method. For the structural parameters Romers’ data obtained by the electron diffraction seems to be nearly correct.