METHOD OF ADJUSTMENT OF VALUE OF CHARGE OF REVERSE RECOVERY OF SEMICONDUCTOR DEVICES WITH PRESET ACCURACY Russian patent published in 1998 - IPC

FIELD: semiconductor technology, manufacture of thyristors and diodes. SUBSTANCE: method includes adjustment of value of charge Q_rr of reverse recovery determined by relation Q_з-ΔQ≤Q_fi≤Q_з+ΔQ, where Q_з is required value of Q_rr for semiconductor devices, Q_fi is factual measured value of Q_rr of i-th semiconductor device, ΔQ is value of permissible deviation of Q_fi from Q_з by way of irradiation of lot of rectifying elements across which values Q_rr(Q_oi) are measured in advance. For given type of semiconductor devices and irradiation modes there is established dependence F of change of Q_rr as function from irradiation dose (Ф) by flux of fast electrons at which irradiation doze (Q_1i) for i-th rectifying element is set proceeding from dependence F in correspondence with difference between Q_oi and Q_з. Q_rr/(Q_oi) is measured in each i-th rectifying element not satisfying relation 1 after irradiation and its own dependence F_i of change of Q_rr from Ф is established. After this repeat irradiation is conducted which dose Ф_2i for i-th rectifying element is set proceeding from F_i corresponding to difference between Q_1i and Q_з. EFFECT: manufacture of semiconductor devices with preset accuracy. 2 tbl