A novel high performance TFS SJ IGBT with a buried oxide layer

Abstract

A novel high performance trench field stop (TFS) superjunction (SJ) insulated gate bipolar transistor (IGBT) with a buried oxide (BO) layer is proposed in this paper. The BO layer inserted between the P-base and the SJ drift region acts as a barrier layer for the hole-carrier in the drift region. Therefore, conduction modulation in the emitter side of the SJ drift region is enhanced significantly and the carrier distribution in the drift region is optimized for the proposed structure. As a result, compared with the conventional TFS SJ IGBT (Conv-SJ), the proposed BO-SJ IGBT structure possesses a drastically reduced on-state voltage drop (V ce(on) ) and an improved tradeoff between V ce(on) and turn-off loss (E off ), with no breakdown voltage (BV ) degraded. The results show that with the spacing between the gate and the BO layer W o = 0.2 µm, the thickness of the BO layer L o = 0.2 µm, the thickness of the drift region L d = 90 µm, the half width and doping concentration of the N-and P-pillars W n = W p = 2.5 µm and N n = N p = 3 × 10 15 cm −3 , the V ce(on) and E off of the proposed structure are 1.08 V and 2.81 mJ/cm 2 with the collector doping concentration N c = 1 × 10 18 cm −3 and 1.12 V and 1.73 mJ/cm 2 with N c = 5 × 10 17 cm −3 , respectively. However, with the same device parameters, the V ce(on) and E off for the Conv-SJ are 1.81 V and 2.88 mJ/cm 2 with N c = 1 × 10 18 cm −3 and 1.98 V and 2.82 mJ/cm 2 with N c = 5 × 10 17 cm −3 , respectively. Meanwhile, the BV of the proposed structure and Conv-SJ are 1414 V and 1413 V, respectively.

Two out of one: revising the diversity of the epiphytic fern genus Scleroglossum (Polypodiaceae, Grammitidoideae) in southern China

“…Wuzhishan population. The Guangxi and Guangdong occurrences have been surveyed in recent years (Zhou and Li 1993, Yan et al 2007, Zhang and Li 2011, Jiang and Liu 2014). Thus, all recorded populations of these ferns in China are arguably stable despite the restriction to isolated localities result in local threats.…”

“…Wuzhishan, Mt. Yinggeling) and Taiwan (North), the genus Scleroglossum was previously recorded to occur in the Nanling Mountains of Guangdong (Yan et al 2007, Zhang and Li 2011), Daming Mountain and Shangsi County in Guangxi (Zhou and Li 1993, Qin and Liu 2010, Jiang and Liu 2014), and Mt. Laojunshan in Yunnan (Lu and Zhang 1994).…”

High performance carrier stored trench bipolar transistor with dual shielding structure

“…Meanwhile, the deep gate trench used in the CSTBT increases the gate-collector capacitance C GC , which slows down the switching speed and increases the switch loss E OFF as well as turn-on loss E ON . [8][9][10][11][12] Therefore, to further improve the device performance, many im-proved CSTBT structures, such as p-type buried layer (PBL) structure, alternated trench IGBT with PBL structure, recessed emitter trench (RET) structure and split gate (SG) structure, have been proposed. [13][14][15][16][17][18][19] Although device performance is significantly improved for these structures, the contradiction between V CEON and E OFF for the CSTBT is still prominent, which limits the further reduction of the device power loss and improvement of the power density.…”

Superjunction nanoscale partially narrow mesa IGBT towards superior performance

“…[1] Thus, the narrowed mesa width in trench IGBT can be an effective way to achieve this theoretical limit. Based on this concept, many structure variations have been presented, such as the advanced CSTBT structure, [2] the micro pattern trench IGBT, [3] the very shallow trench IGBT by the scaling rule theory, [4] the trench IGBT with P-ring structure and point injection effect, [5,6] the fin p-body IGBT, [7] the superjunction (SJ) trench IGBT with buried oxide, [8] and the partially narrow mesa IGBT (PNM-IGBT). [9,10] Among these structures, the V ce(sat) of PNM-IGBT can be very close to the theoretical limit by using a nanoscale mesa width as the hole barrier layer.…”