A SiC MESFET structure is successfully prepared on a semi-insulated 50mm SiC substrate using a hotwall SiC reactor. The doping concentration for the channel layer is about 1.7 × 10^17 cm^-3 , and the thickness is...A SiC MESFET structure is successfully prepared on a semi-insulated 50mm SiC substrate using a hotwall SiC reactor. The doping concentration for the channel layer is about 1.7 × 10^17 cm^-3 , and the thickness is about 0.35μm. An unintentionally n-doped buffer layer is employed between the substrate and the channel layer. A cap layer for Ohmic contact is doped to 10^19cm^-3. MESFET devices are fabricated using inductively coupled plasma etching and other conventional tools. Power devices with a 1mm gate width are measured and a 2W output at 2GHz is obtained.展开更多
4H-SiC MESFETs are fabricated on semi-insulating SiC substrates. Key processes are optimized to obtain better device performance. A microwave power amplifier is demonstrated from a 1mm SiC MESFET for S band operation....4H-SiC MESFETs are fabricated on semi-insulating SiC substrates. Key processes are optimized to obtain better device performance. A microwave power amplifier is demonstrated from a 1mm SiC MESFET for S band operation. When operated at a drain voltage of 64V, the amplifier shows an output power of 4.09W, a gain of 9.3dB,and a power added efficiency of 31.3%.展开更多
A new 125mm UHV/CVD SiGe/Si epitaxy equipment SGE500 capable of commercialization is constructed and device-level SiGe HBT material is grown.A polysilicon emitter (PolyE) double mesa microwave power SiGe HBT showing e...A new 125mm UHV/CVD SiGe/Si epitaxy equipment SGE500 capable of commercialization is constructed and device-level SiGe HBT material is grown.A polysilicon emitter (PolyE) double mesa microwave power SiGe HBT showing excellent low current DC characteristics with β=60@V CE/I C=9.0V/300μA,β=100@5V/50mA,BV CBO=22V,f t/f max=5.4GHz/7.7GHz@3V/10mA is demonstrated.The PolyE SiGe HBT needs only 6 lithographical steps and cancels the growth of the thick emitter epitaxy layer,both of which show great potential for volume production.A 60-finger class-A SiGe linear power amplifer (PA) w ith 22dBm of 1dB compress point output power (P 1dB),11dB of power gain (G p) and 26.1% of power added efficiency (PAE) @900MHz,3.5V/0.2A is demonstrated.Another 120-finger class-A SiGe PA with 33.3dBm (2.1W) of P out,10.3dB of G p and 33.9% of PAE @900MHz,11V/0.52A is also demonstrated.展开更多
Good performance SiGe power amplifiers applicable to wireless communications are demonstrated.The output power can reach more than 30dBm in class B mode.And in class AB mode,the output power at 1dB compression point (...Good performance SiGe power amplifiers applicable to wireless communications are demonstrated.The output power can reach more than 30dBm in class B mode.And in class AB mode,the output power at 1dB compression point ( P 1dB ) is 24dBm,the output third order intercept (TOI) power is 39dBm under V cc of 4V.The highest power added efficiency (PAE) and PAE at 1dB compression point are 34% and 25%,respectively.The adjacent channel power rejection for CDMA signal is more than 42dBc,which complies with IS95 specification.展开更多
The structure and microwave characteristics of low-voltage SiGe power HBTs are given.With this structure,the device can operate in a low-voltage and high-current state.By using an interdigital emitter strip layout and...The structure and microwave characteristics of low-voltage SiGe power HBTs are given.With this structure,the device can operate in a low-voltage and high-current state.By using an interdigital emitter strip layout and the operating voltage ranging from 3 to 4V,the output power in Class C operation can reach 1 65W at 1GHz,with the gain of 8dB.The highest collector efficiency is 67 8% under 3V.展开更多
文摘A SiC MESFET structure is successfully prepared on a semi-insulated 50mm SiC substrate using a hotwall SiC reactor. The doping concentration for the channel layer is about 1.7 × 10^17 cm^-3 , and the thickness is about 0.35μm. An unintentionally n-doped buffer layer is employed between the substrate and the channel layer. A cap layer for Ohmic contact is doped to 10^19cm^-3. MESFET devices are fabricated using inductively coupled plasma etching and other conventional tools. Power devices with a 1mm gate width are measured and a 2W output at 2GHz is obtained.
文摘4H-SiC MESFETs are fabricated on semi-insulating SiC substrates. Key processes are optimized to obtain better device performance. A microwave power amplifier is demonstrated from a 1mm SiC MESFET for S band operation. When operated at a drain voltage of 64V, the amplifier shows an output power of 4.09W, a gain of 9.3dB,and a power added efficiency of 31.3%.
文摘A new 125mm UHV/CVD SiGe/Si epitaxy equipment SGE500 capable of commercialization is constructed and device-level SiGe HBT material is grown.A polysilicon emitter (PolyE) double mesa microwave power SiGe HBT showing excellent low current DC characteristics with β=60@V CE/I C=9.0V/300μA,β=100@5V/50mA,BV CBO=22V,f t/f max=5.4GHz/7.7GHz@3V/10mA is demonstrated.The PolyE SiGe HBT needs only 6 lithographical steps and cancels the growth of the thick emitter epitaxy layer,both of which show great potential for volume production.A 60-finger class-A SiGe linear power amplifer (PA) w ith 22dBm of 1dB compress point output power (P 1dB),11dB of power gain (G p) and 26.1% of power added efficiency (PAE) @900MHz,3.5V/0.2A is demonstrated.Another 120-finger class-A SiGe PA with 33.3dBm (2.1W) of P out,10.3dB of G p and 33.9% of PAE @900MHz,11V/0.52A is also demonstrated.
文摘Good performance SiGe power amplifiers applicable to wireless communications are demonstrated.The output power can reach more than 30dBm in class B mode.And in class AB mode,the output power at 1dB compression point ( P 1dB ) is 24dBm,the output third order intercept (TOI) power is 39dBm under V cc of 4V.The highest power added efficiency (PAE) and PAE at 1dB compression point are 34% and 25%,respectively.The adjacent channel power rejection for CDMA signal is more than 42dBc,which complies with IS95 specification.
文摘The structure and microwave characteristics of low-voltage SiGe power HBTs are given.With this structure,the device can operate in a low-voltage and high-current state.By using an interdigital emitter strip layout and the operating voltage ranging from 3 to 4V,the output power in Class C operation can reach 1 65W at 1GHz,with the gain of 8dB.The highest collector efficiency is 67 8% under 3V.
