U-series IGBT Modules (1, V) Yuichi Onozawa Shinichi Yoshiwatari Masahito Otsuki 1. Introduction Power conversion equiment such as general-use inverters and uninterrutible ower sulies (UPSs) is continuously challenged by demands for higher efficiency, smaller size, lower cost and lower noise. Accordingly, ower-converting elements for inverter circuits are also required to have higher erformance and lower cost. At resent, IGBTs (insulated gate biolar transistors) are the main ower-converting elements used because of their low loss and easy drive circuit imlementation. After commercializing the IGBT in 1988, Fuji Electric has made efforts to imrove the IGBT in ursuit of lower loss and lower cost. This aer introduces fifth generation IGBT modules (U-series), and focuses on the 1, V series used mainly in 4 V AC ower lines overseas. Adotion of a trench gate structure and a field sto (FS) structure has resulted in a large imrovement in the trade-off characteristics of fifth generation IGBTs comared with those of the fourth generation IGBT (Sseries). 2. Features of the New IGBTs Figure 1 shows the trade-off relation of the saturation between the collector and emitter (V CE (sat) ) and the turn-off loss of the newly develoed IGBT (trench FS-IGBT). From this figure, it can be seen that the trade-off of the 1, V U-series IGBT is dramatically imroved comared to that of the former generation S-series IGBT [laner NPT (non unch through) -IGBT]. This dramatic imrovement in characteristics has been achieved through adoting a field sto structure, evolved from an advanced NPT configuration, and a trench gate structure, acquired during develoment of MOSFETs (metal oxide semiconductor field effect transistors). Each of these structures is described below. 2.1 Field sto structure Figure 2 shows outut characteristics and Fig. 3 shows comarison of cross section of unit cells of a lanar NPT-IGBT and a lanar FS-IGBT. An NPT- IGBT requires a thick drift layer so that the deletion layer does not contact the collector side during turn-off. The FS-IGBT does not, however, require such a thick drift layer as the NPT because a field sto layer to sto the deletion layer has been fabricated in the FS-IGBT and accordingly V CE (sat) can be lowered for the FS- IGBT. Furthermore, the FS-IGBT has fewer excess carriers because of its thinner drift layer. Moreover, Fig.1 Trade-off between V CE (sat) and turn-off loss Fig.2 Outut characteristics Turn-off loss (mj/ulse) 25 15 1 Trench FS-IGBT 1, V/15 A V CC =6 V, I C =15 A, V G =+15 V/ 15 V Trench FS-IGBT Planar NPT-IGBT current JC (A/cm 2 ) 16 1 8 4 Trench FS-IGBT Planar NPT-IGBT 5 1.2 1.4 1.6 1.8 2. 2.2 V CE(sat) (V) 2.4 2.6 2.8.5 1. 1.5 2. 2.5 3. VCE(sat) (V) U-series IGBT Modules (1, V) 115
Fig.3 Comarison of cross sections of unit cells of a lanar NPT-IGBT and a lanar FS-IGBT Fig.5 Short-circuit waveforms Short-circuit test (at V CC = 8 V and T j = ) V GE n- (Drift layer) n- (Drift layer) VGE = VCE Field sto layer n I C TW = 24.6 µs E SC = 8.36 J Deletion layer V GE, Ic= (a) Planar NPT-IGBT (b) Planar FS-IGBT 1, V/15 A Trench FS-IGBT VCE : V/div, IC : 5 A/div, Time : 5 µs/div, VGE : V/div Fig.4 Comarison of cross sections of IGBT unit cells Fig.6 Comarison of turn-on waveforms Layer insulation film Layer insulation film Conventional PiN New FWD Turn-on (at T j = ) 1, V/5 A VCE : V/div, IC : 25 A/div, Time : ns/div n- n- (a) Planar FS-IGBT (b) Trench FS-IGBT TR16 T1 T2 the FS-IGBT can achieve reduced turn-off loss because the remaining width of its neutral region is small when its deletion layer is comletely extended. Fig.7 Comarison of FWD outut characteristics 2.2 Trench gate structure Figure 4 shows a cross section of a trench FS-IGBT. By adoting a trench gate structure, channel density can be increased and V CE (sat) can be significantly lowered because resistance in the J FET art, which was roblematic for lanar IGBTs when cell density increased, can be reduced to zero. On the other hand, the high channel density of the trench IGBT causes a roblem of low short-circuit caacity. However, the trench gate structure otimizes the total channel length to realize high short-circuit caacity without sacrificing V CE (sat) (Fig. 5). Forward current (A) 1 8 6 4 New FWD 1, V/75 A FWD Forward current (A).5 1. 1.5 2. 2.5 3. 3.5 Forward (V) 1 8 6 4 Conventional PIN.5 1. 1.5 2. 2.5 3. 3.5 Forward (V) 116 Vol. 48 No. 4 FUJI ELECTRIC REVIEW
Table 1 Characteristics of the 1, V U-series IGBT modules (a) Absolute maximum ratings (at T c = 25 C unless otherwise secified) Item -emitter -emitter current Maximum loss Junction Preserving Isolation (ackage) Screw fastening torque Item emitter leakage current -emitter leakage current -emitter threshold emitter saturation Inut caacitance Outut caacitance Reverse transfer caacitance Turn-on time Turn-off time Diode forward Reverce recovery time Symbol Condition Max. rating Unit V CES 1, V V GES ± V I C I C ulse P C 1 device 6 W T j 15 C T stg T j =25 C 15 Continous T j =8 C 1 1 ms T j =25 C 3 T j =8 C I C 1 I C ulse 1 ms 4 to +125 V iso AC : 1 min 2,5 V Mounting 3.5 Terminals 3.5 Symbol A C Nm (b) Electrical characteristics (at T c = 25 C unless otherwise secified) I V GE = V, CES 1. ma V CE =1, V V CE = V, I GES.2 µa V GE =± V V CE = V, V GE(th) 7. V I C =1 ma V CE(sat) (Terminal) V CE(sat) (Chi) V F (Terminal) V F (Chi) V GE = 15 V, I C = 1 A I F = 1 A Condition Characteristics Unit min. ty. max. T j =25 C 1.95 T j = 2.2 T j =25 C 1.75 T j = 2. C ies 13.3 C oes V GE = V, V CE =1 V.8 f =1 MHz C res 1.2 t on 1.2 V CC =6 V t r I C =1 A.6 t off V GE =±15 V 1. R g =4.7 Ω t f.3 T j =25 C 2. T j = 2. T j =25 C 1.8 T j = 1.8 V nf t rr I F =1 A.35 µs µs V (c) Thermal resistance characteristics Characteristics Item Symbol Condition Unit min. ty. max. Thermal resistance IGBT.21 R (1 device) th(j-c) FWD.33 C/W Thermal resistance R between case and fins th(c-f).5 Table 2 Rated (V) 1, 1, V U-series IGBT modules Rated Package current Tyes (A) Small PIM 1 7MBR1UE1 15 7MBR15UE1 1 7MBR1UA1 EP2 15 7MBR15UA1 25 7MBR25UA1 EP3 HEP2 HEP3 7in1 (M631 or P611) M232 M233 M234 35 7MBR35UB1 5 7MBR5UB1 75 7MBR75UB1 75 7MBI75UD-1 1 7MBI1UD-1 15 7MBI15UD-1 75 2MBI75UA-1 1 2MBI1UA-1 15 2MBI15UB-1 2MBIUB-1 2MBIUC-1 3 2MBI3UC-1 M235 3 2MBI3UD-1 M238 Large caacity module 35 7MBR35UD1 New PC2 75 6MBI75UA-1 New PC3 35 7MBR35UA1 1 7MBR1UC1 15 7MBR15UC1 25 7MBR25UC1 35 7MBR35UC1 5 7MBR5UD1 75 7MBR75UD1 75 6MBI75UB-1 1 6MBI1UB-1 15 6MBI15UB-1 75 6MBI75UC-1 1 6MBI1UC-1 15 3MBI15UC-1 New PC2 15 3MBI15U-1 15 2MBI15UA-1 3 2MBI3UE-1 45 2MBI45UE-1 225 6MBI225U-1 3 6MBI3U-1 45 6MBI45U-1 Sale date Aril 3 U-series IGBT Modules (1, V) 1
Fig.8 Catalogue of ackages of 1, V U-series PIM 6 in 1 7 in 1 2 in 1 EP2 PC3 122 HEP2 M232.5 M5 11.5 93 16 16 16 45.5 EP3 122 Large caacity module M6 HEP3 M233 122 11 U V W 31.4 62 5.5.5 15 137 62 5.5 122 11 5 + 5 + 5 + 162 Small PIM1 M631 118 M235 57 Small PIM2 65.6 33.4 22.5 51 23.5 3 3 3 92 92 18 11 3 85 22 B P N U V W 23.5 7 M238 8 62 45 34 3. Features of the New FWDs Fig.9 Correlation among 1, V U-series Rated current 5A 1A 15A 25A 35A 5A 75A 1A 15A A 3A 45A 6A Series (5.5kW) (11kW) (22kW) (4kW) (75kW) Small PIM Small PIM PIM EP2/HEP2 EP3/HEP3 6 in 1 New PC3 with a thermal sensor (6 in 1) M631 with a thermal sensor (7 in 1) Large caacity module (6 in 1) 2 in 1 /1 in 1 PIM/ 6 in 1 For vector control EP (N-line oen) M232 New PC (with shunt resistance) M238 M233 M235 M138 As IGBT switching seeds have increased, the accomanying vibration at the time of switching has become a significant roblem. Fuji Electric succeeded in realizing soft recovery to suress the vibration even at a high di/ dt by otimizing the surface structure and bulk imurities rofile of the FWDs (free wheeling diodes) (Fig. 6). Moreover, a newly develoed FDW has been made suitable for arallel oeration by otimizing a lifetime killer to achieve a ositive coefficient of the outut characteristics (Fig. 7). 4. 1, V U-series IGBT Modules and Characteristics Characteristics of 1, V U-series IGBT modules and an overview of U-series are resented in Tables 1 118 Vol. 48 No. 4 FUJI ELECTRIC REVIEW
and 2, resectively. A catalog of ackages available in this series is shown in Fig. 8 and the correlation among the 1, V U-series IGBT modules is shown in Fig. 9. 5. Conclusion An overview of the 1, V U-series IGBT modules has been resented. The IGBTs of this series are extremely low loss devices and we believe they will make imortant contributions to the realization of smaller size and lower loss equiment. Fuji Electric intends to continue to work toward realizing higher erformance and higher reliability devices and to contribute to the develoment of ower electronics. Reference (1) Laska, T. et al. The Field Sto IGBT (FS IGBT) A New Power Device Concet with a Great Imrovement Potential. Proc. 12th ISPSD., 355-358. U-series IGBT Modules (1, V) 119
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