The Impact Of Epitaxy Growth To Lithography Overlay

With the development of semiconductor technology, our daily life and semiconductor increasingly close relationship. Whether in the consumable electronic product like computer and mobile phone, or in the sophisticated technology like medical and aviation, semiconductor chipis inseparable. But with the development and progress of society, our demand to those electronic products are increasingly, we hope that the volume of the mobile phone can be smaller while speed can be faster and the computer could be cheaper while performance can be higher, the human motivation source is actually their own needs. So after the1990s, the semiconductor industry got on a new step every two to three years. While the electronic products become unprecedented prosperity and abundance.As the requirement of electronic products to chip performance become higher, the new technology Expitaxy has been paid more and more attention. The current product, not only have very high requirement on follow-up process, but also have very key specification of raw wafer preparation, only in this way, the final product can meet the requirements. And the Epitaxy process can provide almost pure silicon layer, can greatly enhance the performance of the device, although to a certain extent, will increase the cost, but considered the advantages, this cost is acceptable. However, any technology has its own problems and shortcomings, Epitaxy process is no exception. The Epitaxy process will bring some of the inevitable defects, and these defects will influence other semiconductor process steps. How to control these effects will be the key point.In this paper, the microelectronic technology, the integrated circuit, semiconductor manufacturing process were outlined a simple. Then the basic process of lithography and overlay principle were introduced, finally the epitaxial process principle, process, characteristics, defects and other related knowledge were introduced with emphasis. And I use one actual production examples to study the pattern shift on lithography overlay and countermeasures. In advanced technology, the application rate of Epitaxy is very high and the lithography overylay requirement is also high, so the method has widely applied significance.