Apparatus for coating substrate devices

Abstract

The present apparatus has a movable table with apertures therein. In each aperture there is loaded a carrier device and each carrier holds a substrate to be coated. The carriers are advanced in a step-like fashion to a loading position under a vertical hollow cylinder. When a carrier is in the loading position, a piston is moved upward, passing through the aperture, pushing the carrier into the hollow cylinder. Each carrier has an O-ring on its periphery and the O-ring is squeezed against the cylinder wall to form a seal. Each carrier pushes against the one above it to advance a column of carriers upward in the hollow cylinder. In this way, the carriers, and the substrates they hold, pass through the hollow cylinder. Along the cylinder there are vacuum stations which act to pump down and degas the substrates. The degassed substrates eventually emerge from the upper end of the cylinder into a vacuum chamber, whereat they are coated by sputtering, or the like. The vacuum level in the coating chamber is not as low as the vacuum level at the vacuum stations along the cylinder. Accordingly, gasses in the coating chamber tend to try to escape into the vertical cylinder but are stopped by the O-ring seals on the carriers. Hence the coating chamber is not contaminated. The substrates are transmitted through the coating chamber, coated, and withdrawn therefrom through a second hollow cylinder.