Circulating Tumor Cells (CTCs) separation from the peripheral blood is an advantageous method compared to conventional tumor biopsy for diagnosis and prognosis of cancerous patients. Also, label-free separation of CTCs from the blood projected an attractive output due to its high throughput, low cost, and no need for an expert for the test. Among different label-free methods, Vortex technology is a high purity method that could separate CTCs from 7.5ml of blood in a rapid test (less than an hour) with a high enrichment ratio, concentrating the intact viable CTCs and opens new windows for drug tests and personal treatments. In the classic design of vortex chip, besides its advantages, the efficiency, which shows the percent of separated target particles compared to the total number, is still challenging. The automated instrument VTX-1 reintroduces the sample to the chip multiple times to improve the total efficiency from 3 to 7 times. Here we modified the geometry of the chip introduced by Paie to separate cells in a single-step process. We elevated the chips reservoirs' height to achieve higher efficiency. A 2-step lithography design was employed to elevate the reservoirs' height, despite the same channels. Modified reservoirs affect the streamlines of the vortex, tend the vortex to form in lower Reynolds number, reduce the deformation of the PDMS chip, and capacitate the particles to orbit not just in 2D but 3D paths. Using this design helped the separation process to reduce particle-particle interactions and provide a larger volume to capture more target particles in each reservoir. Results show that elevating the reservoirs' height could improve the efficiency of the columned vortex chip from 60 to 75% for 20μm microbeads separation from the buffer in one step.