Abstract:
A PROCESS IS DISCLOSED HEREIN FOR THE USE OF NITROGEN IN A NUCLEATION PROCESS FOR THE CHEMICAL VAPOR DEPOSITION OF POLYCRYSTALLINE SILICON FROM SICL4. AFTER ESTABLISHING THE DESIRED FURNACE TEMPERATURE AT A SINGLE TEMPERATURE LYING WITHIN THE RANGE OF 900*C. TO 1200*C., THE SYSTEM IS PURGED WITH NITROGEN AND HYDROGEN. AFTER THE SYSTEM HAS BEEN PURGED, THE NITROGEN FLOW IS STOPPED AND THE SICL4 FLOW IS STARTED SIMULTANEOUSLY. THE OVERLAP OF NITROGEN AND SICL4 WITHIN THE SYSTEM CAUSES NUCLEATION FROM WHICH A VERY FINEGRAIN LAYER OF POLYCRYSTALLINE SILICON IS GROWN.
Abstract:
A method for etching a groove along a junction between regions of semiconductor material having different dopant concentrations to delineate or isolate the regions forming the junction. Standard concentrations of sirtl etch are used in conjunction with infrared radiation. Wafers in a holder are placed in a container of sirtl etch and exposed to infrared radiation. Preferential etching creates a groove at the semiconductor junction.