Abstract: A semiconductor device having an n-type layer of gallium nitride that is doped with silicon and has a resistively ranging from 3×10−1 &OHgr;cm to 8×10−3 &OHgr;cm or a carrier concentration ranging from 6×1016/cm3 to 3×1018/cm3.

Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n.sup.+ -layer (3) of high carrier (n-type) concentration, a Si-doped (Al.sub.x3 Ga.sub.1-x3).sub.y3 In.sub.1-y3 N n.sup.+ -layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Al.sub.x2 Ga.sub.1-x2).sub.y2 In.sub.1-y2 N emission layer (5), and a Mg-doped (Al.sub.x1 Ga.sub.1-x1).sub.y1 In.sub.1-y1 N p-layer (6). The AlN layer (2)--is 500 .ANG. in thickness. The GaN N.sup.+ -layer (3) is about 2.0 .mu.m in thickness and has an electron concentration of about 2.times.10.sup.18 /cm.sup.3. The n.sup.+ -layer (4) is about 2.0 .mu.m in thickness and has an electron concentration of about 2.times.10.sup.18 /cn.sup.3. The emission layer (5) is about 0.5 .mu.m in thickness. The p-layer 6 is about 1.0 .mu.m in thickness and has a hole concentration of about 2.times.10.sup.17 /cm.sup.3. Nickel electrodes (7, 8) are connected to the p-layer (6) and n.sup.

Abstract: Disclosed is a light-emitting semiconductor device which comprises an N-layer of N-type nitrogen-Group III compound semiconductor satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0 and x=y=0, a P-layer of P-type nitrogen-Group III compound semiconductor satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0 and x=y=0 and a Zn doped semi-insulating I-layer of nitrogen-Group III compound semiconductor satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0 and x=y=0. The semi-insulating I-layer has a 20 to 3000 .ANG. thickness and can emit light in the range of 485 to 490 nm. By employing the I-layer, the light-emitting diode as a whole can emit light in the range of 450 to 480 nm.

Abstract: A light-emitting diode or laser diode is provided which uses a Group III nitride compound semiconductor satisfying the formula (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y N, inclusive of 0.ltoreq.x.ltoreq.1, and 0.ltoreq.y.ltoreq.1. A double hetero-junction structure is provided which sandwiches an active layer between layers having wider band gaps than the active layer. The diode has a multi-layer structure which has either a reflecting layer to reflect emission light or a reflection inhibiting layer. The emission light of the diode exits the diode in a direction perpendicular to the double hetero-junction structure. Light emitted in a direction opposite to the light outlet is reflected by the reflecting film toward the direction of the light outlet. Further, the reflection inhibiting film, disposed at or near the light outlet, helps the release of exiting light by minimizing or preventing reflection. As a result, light can be efficiently emitted by the light-generating diode.

Abstract: A light-emitting semiconductor device having an improved metal electrode and semiconductor structure that lowers the driving voltage of the device. The device has a hetero p-n junction structure. This structure includes: (1) an n-layer having n-type conduction and a Group III nitride compound semiconductor satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0, and x=y=0; (2) a p-layer having p-type conduction and a Group III nitride compound semiconductor satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0, and x=y=0; and (3) an emission layer disposed between the n-layer and the p-layer. The device also has a metal electrode and a contact layer that is disposed between the p-layer and the metal electrode. The contact layer is doped with an acceptor impurity more heavily that is the p-layer. The acceptor impurity may be magnesium (Mg). The contact layer may be doped within the range of 1.times.10.sup.20 /cm.sup.3 to 1.times.10.sup.2l /cm.sup.

Abstract: A light-emitting semiconductor device using a gallium nitride compound semiconductor (Al.sub.x Ga.sub.1-x N) having an i.sub.L -layer of insulating gallium nitride compound semiconductor (Al.sub.x Ga.sub.1-x N, inclusive of x=0) containing a low concentration of p-type impurities. An i.sub.H -layer of insulating gallium nitride compound semiconductor (Al.sub.x Ga.sub.1-x N, inclusive of x=0) containing a high concentration of p-type impurities is adjacent to the i.sub.L -layer. An n-layer of n-type gallium nitride compound semiconductor (Al.sub.x Ga.sub.1-x N, inclusive of x=0) of low carrier concentration is adjacent to the i.sub.L -layer. An n.sup.+ -layer of n-type gallium nitride compound semiconductor (Al.sub.x Ga.sub.1-x N, inclusive of x=0) of high carrier concentration doped with n-type impurities is adjacent to the n-layer.

Abstract: A light-emitting semiconductor device (10) consecutively has a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n.sup.+ -layer (3) of high carrier (n-type) concentration, a Si-doped (Al.sub.X2 Ga.sub.1-x2).sub.y2 In.sub.1-y2 N n.sup.+ -layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Al.sub.x1 Ga.sub.1-x1).sub.y1 In.sub.1-y1 N emission layer (5), and a Mg-doped (Al.sub.x2 Ga.sub.1-x2).sub.y2 In.sub.1-y2 N p-layer (6). The AlN buffer layer (2) has a 500 .ANG. thickness. The GaN n.sup.+ -layer (3) is about 2.0 .mu.m thick and has a 2.times.10.sup.18 /cm.sup.3 electron concentration. The n.sup.+ -layer (4) is about 2.0 .mu.m thick and has a 2.times.10.sup.18 /cm.sup.3 electron concentration. The emission layer (5) is about 0.5 .mu.m thick. The p-layer 6 is about 1.0 .mu.m thick and has a 2.times.10.sup.17 /cm.sup.3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n.sup.+ -layer (4), respectively.

Abstract: A light-emitting semiconductor device (100) suitable for use in multi-color flat panel displays includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n.sup.+ -layer (3) of high carrier (n-type) concentration, a Si-doped (Al.sub.x2 Ga.sub.1 -x.sub.2).sub.y2 In.sub.1-2 N n.sup.+ -layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped p-type (Al.sub.x1 Ga.sub.1-x1).sub.y1 In.sub.1-y1 N emission layer (5), and a Mg-doped (Al.sub.x2 Ga.sub.1-x2).sub.y2 In.sub.1-y2 N p-layer (6). The AlN layer (2) has a 500 .ANG. thickness. The GaN n.sup.+ -layer (3) is about a 2.0 .mu.m thick and has a 2.times.10.sup.18 /cm.sup.3 electron concentration. The n.sup.+ -layer (4) is about a 2.0 .mu.m in thickness and has a 2.times.10.sup.18 /cm.sup.3 electron concentration. The emission layer (5) is about 0.5 .mu.m thick. The p-layer 6 is about 1.0 .mu.m thick and has a 2.times.10.sup.17 /cm.sup.3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n.sup.

Abstract: A sapphire wafer is sliced off parallel to a plane "a" {1120} so that patterns on its top surface are rectangular in shape as defined by an axis "c" (0001) and an axis "m" (1010). The sapphire wafer is fixed on a table. A scriber blade that is coated with synthetic diamond scribes the surface of the sapphire wafer so that scribe lines are formed in a checkered pattern. One of the scribe lines is inclined from axis "c" (001) by 20 to 70 degrees in a clockwise direction and the other scribe line is inclined from the axis "c" (001) by 20 to 70 degrees in a counterclockwise direction. After scribing, pressure is applied by a roller along the scribe lines so as to cause the sapphire wafer to break into a sapphire chip. The yield of sapphire chips is increased by the use of this method because chipping is less likely to occur.

Abstract: Disclosed herein are (1) a light-emitting semiconductor device that uses a gallium nitride compound semiconductor (Al.sub.x Ga.sub.1-x N) in which the n-layer of n-type gallium nitride compound semiconductor (Al.sub.x Ga.sub.1-x N) is of double-layer structure including an n-layer of low carrier concentration and an n.sup.+ -layer of high carrier concentration, the former being adjacent to the i-layer of insulating gallium nitride compound semiconductor (Al.sub.x Ga.sub.1-x N); (2) a light-emitting semiconductor device of similar structure as above in which the i-layer is of double-layer structure including an i.sub.L -layer of low impurity concentration containing p-type impurities in comparatively low concentration and an i.sub.