Patent ID: 6214708
Filing Date: 2001-04-10
Classification: H01L

Abstract:
A method for diffusing Zn into III-V group compound semiconductor crystals comprising the steps of:preparing a horizontal, elongating base plank having an exhaustion hole and a wafer-storing cavity;inserting an object group III-V compound wafer into the wafer-storing cavity of the base plank;preparing a slider consisting of a frame having serially aligning M rooms (M.gtoreq.1) with an open bottom and a rack being separated from each other by (M-1) partition walls, a non-doped capping wafer affixed at a front end of the frame and a cap plate for covering a top of the frame;taking the cap plate off the top of the slider;putting one of a Zn-diffusion source and a V element source turn by turn on each rack of the serially-aligning rooms;fixing the cap plate on the top of the frame for covering the open top of the slider;laying the slider on the base plank;affixing a manipulating bar to the slider;putting the base plank into a tube;making an inner space of the tube vacuous;carrying the slider by the manipulating bar at spots where each room lies in turn just above the exhaustion hole for evacuating each room through the exhaustion hole;carrying the slider by the manipulating bar to a spot for covering the object wafer with the capping wafer of the slider;inserting the tube into a furnace with heaters;heating the base plank, the object wafer and the slider;moving the slider at a spot for covering the object wafer with the room having the diffusion source when the temperature attains to a pertinent temperature for diffusion;diffusing the Zn atoms into the object wafer for a determined time at a pertinent temperature in the diffusion source room as a first diffusion process;moving the slider to a spot for covering the object wafer with the room having the V element source;changing the temperature of the object wafer to a temperature pertinent to following diffusion by regulating power of the heaters;moving the slider to a spot for covering the object wafer with the following room having the diffusion source;diffusing the Zn atoms into the object wafer for a determined time at a pertinent temperature in the diffusion source room as a second diffusion process;repeating necessary cycles of the steps of changing temperature and the steps of the Zn-diffusion; andfinally moving the slider at a spot away from the object wafer for cooling the object wafer in a state separating from the diffusion room of the slider.