(sc) a machine which steps a reticle directly onto the wafer. A reticle can be produced at lower defect level and with tighter dimensional control than an entire mask, resulting in wafer images having fewer defects. Alignment of reticle to wafer is accomplished by reflecting a laser beam through a special reticle pattern (alignment target) and off a corresponding pattern on the wafer.
a device, similar to a slide projector or a photographic enlarger, that is used in
a kind of fancy slide projector
A photolithography machine used to expose a pattern on a wafer by shining light through a reticle (a glass plate containing a pattern etched in chrome). Since it cannot accurately expose the entire wafer at once, a stepper exposes an area of a smaller size and keeps repeating this until the whole wafer is covered. This process is called step and repeat. An eight inch wafer might need about 80 fields for full exposure.
Equipment used to transfer a reticle pattern on to a wafer.
Equipment used to transfer a reticle (mask) pattern onto a wafer.
A photolithography tool used in the production of semiconductor devices, thin film recording heads, micromachined devices and so forth. Also referred to as a step-and-repeat projection aligner, stepper works by transferring the image of a circuit or component from a master photomask image onto a small portion of the wafer surface. The substrate is then moved or stepped, and the image is exposed once again onto another area of the wafer. This process is repeated until the entire wafer surface is exposed.
A stepper is a device used in the manufacture of integrated circuits (ICs) that is similar in operation to a slide projector or a photographic enlarger. Steppers are an essential part of the complex process, called photolithography, that creates millions of microscopic circuit elements on the surface of tiny chips of silicon. These chips form the heart of ICs such as computer processors, memory chips, and many other devices.