| 摘要 |
PROCEDURE FOR FABRICATING DEVICES INVOLVING DRY ETCHING The present invention relates to a process for fabricating a device comprising the steps of forming a resist mask on a substrate, etching the substrate to form a plurality of etch pits defining a plurality of features by inducing reaction of the substrate with energetic species and completing the device. The redeposition of material on the side walls of the etch pit ocours during the etching. The process includes at least one step chosen from the group of steps consisting of, 1) locally compensating for the effect of the redeposition on the conformation of the sidewall, 2) when the redeposition material presents a barrier to isotropic etching in the sukstrate, contacting the etching species with the resist mask so that the angle formed between a) a tangent to the resist mask at the point the resist mask intercepts the substrate and (b) a perpendicular to the substrate at the point is less than arctan (X/Y), where X is the horizontal rate of the redeposition at the point and Y is the etchant rate of the substrate, and (3) limiting, when the redeposited material presents a barrier to isotropic etching in the subatrate, the contact angle between the momentum direction of the etchant species and a tangent to the redeposition material at all points on the resistant redeposition material serving to mask the sidewalls so that the contact angle is less than arctan (X/Z), where X is as defined in step 2), where Z is the etchant rate of the redeposited material in a direction parallel to the etchant species momentum direction. |
