f is the scan rate and s is the number of line-scanning

within one scanning process. Thus, the feeding velocity of the slow-scanning axis of the AFM tip (V tip ) can be expressed by Equation 1. Moreover, the length of the this website nanochannel (L) is the distance traveled by the high-precision stage. (1) The two machining cases mentioned above are described as follows. Matching relations between V tip and V stage under the condition of the stage motion and the feed rate in the same direction In this condition as shown in Figures 2 and 3, the direction of the feeding velocity and the moving direction of the high-precision stage are both along the positive direction of x axis. The dotted and solid lines represent the previous and the following machining states, respectively. In terms of the velocity of the high-precision Cyclopamine clinical trial stage (V stage) comparing with V tip, the machining process in this situation can be divided into two scenarios as follows: Figure 2 Schematic of the nanochannel scratching with V stage and V tip in the same DAPT chemical structure direction when V stage   <  V tip. ( a ) Schematic of the machining state after one AFM scanning cycle. ( b ) Schematic of the equivalent movement of AFM

tip relative to the stage. Schematic of the machining state after two AFM scanning cycle ( c ) when V stage < 0.5 V tip and ( d ) V stage > 0.5 V tip. ( e ) Schematic of the cross section of the machined nanochannel with the typical condition of N = 0 Thiamine-diphosphate kinase when V stage < 0.5V tip. ( f ) Schematic of the cross section of the machined nanochannel when V stage > 0.5V tip. Figure 3 Schematic of the nanochannel scratching with V stage and V tip in the same direction when V stage   >  V tip . Schematic of the machining state after ( a ) one and ( b ) two AFM scanning cycle. ( c ) Schematic of the cross section of the machined nanochannel. (1) When V stage < V tip, the schematic of the machining process is shown in Figure 2. The tip scanning cycle and the high-precision stage movement are proceeding at the same time. As shown in Figure 2a, the

tip moves from the start position 1 to the final position 2 to finish one tip scanning cycle and the blue region represents the machined area in one AFM scanning cycle. The length of the machined region in one AFM scanning cycle (L C) can be expressed by Equation 2. Then the tip returns to the initial position 1 to start the next scanning process. Considering the relative movement between the AFM tip and the stage, the equivalent movement of AFM tip relative to the stage is in the positive direction of x axis with a velocity of V tip - V stage as shown in Figure 2b. The path of the equivalent movement of the AFM tip is a → b → c → d. The tip moves from b to c caused by the tip finishing a scanning cycle to start a new cycle. The displacement from b to c is L tip which is the scan size of the scanning. Thus, the two adjacent scratched regions are all in the area with the length of L tip.