摘要:
In a laser of such type that the distribution of the effective refractive index varies in a direction which is along the face of its active layer and perpendicular to the direction of the laser light transmission, thereby defining the active region to be between a pair of refractive index changing zones, the refractive indexes of a pair of end surfaces of a laser resonator (i.e. the active region) is made smaller than the intrinsic refractive indexes of the cleavage face of the active layer.
摘要:
A very narrow current injection region (16") is made by means of terrace-shaping of the surface of the current limiting layer (13) forming a step thereon, the current limiting layer being on the epitaxially grown double hetero structure layers (10, 11 and 12) including the active layer (11). By so terrace-shaping, when Zn as a p-type impurity to form the current injection region (16) is diffused from the surface of the current limiting layer (13), the diffused region is formed to have a deeper part (16") and a shallower part (16'), and the deeper part (16") can be made very narrow by selecting the position of the stripe-shaped diffused region with respect to the step (14).
摘要:
The invention provides a chemical etching method for a semiconductor device, which comprises a step of forming a first layer of Ga.sub.1-x Al.sub.x As (0.ltoreq.x . The slope angle of etch face of the second layer depends on the mol fraction y of the second layer, and the slope angle of etch face of the first layer depends on the mol fraction y of the second layer and the mol fraction x of the first layer. These facts are best utilized in the invention so that the etch profile of the first layer may have a desired slope angle. By utilizing this chemical etching method it is possible to produce by chemical etching a semiconductor laser having a flat cavity facet perpendicular to a junction; it is also possible to provide an inner stripe type semiconductor laser having grooves whose side walls are perpendicular.
摘要翻译:本发明提供一种用于半导体器件的化学蚀刻方法,其包括形成具有表面(100)的第一层Ga 1-x Al x As(0 的方向化学蚀刻所述层的步骤。 第二层的蚀刻面的倾斜角取决于第二层的摩尔分数y,第一层的蚀刻面的倾斜角取决于第二层的摩尔分数y和第一层的摩尔分数x 层。 这些事实在本发明中最好地利用,使得第一层的蚀刻轮廓可以具有期望的倾斜角。 通过利用这种化学蚀刻方法,可以通过化学蚀刻具有垂直于结的平坦腔面的半导体激光器来制造; 也可以提供具有侧壁垂直的槽的内条型半导体激光器。
摘要:
In a semiconductor laser of terraced substrate type, comprising on a terraced substrate (11) of n-GaAs substrate, a first clad layer (12) of n-GaAlAs, an active layer (13) of non-doped GaAlAs, a second clad layer (14) of p-GaAlAs and a current limiting layer (15) of n-GaAs, and further thereon a thick overriding layer (19) of n-GaAlAs with strip shaped opening (191), are epitaxially formed, and a current injection layer (16) is formed by Zn diffusion through the opening (191) in a manner one corner (161) of the injection front penetrate the current limiting layer (15) and reaches the second clad layer (14). By means of thick overriding layer (19), shortcircuiting between the active layer (13) and a p-side electrode (7) is prevented.
摘要:
On an n-type semiconductor substrate having a ridge part of stripe-shaped pattern, the following layers are formed by liquid phase sequential epitaxial growth: an undoped active layer; a p-type clad layer; and an n-type isolation layer. Thereafter, a Cd impurity is diffused in the isolation layer in a stripe-shaped pattern at the position above the ridge part, thereby forming a p+-type conduction region in the central part of the isolation layer. By forming the stripe-shaped ridge part on the substrate overriding the active layer, the injected current is effectively confined to the lasing region which is the thinner part of the active layer and is on the ridge part. Therefore the threshold current is decreased. Accordingly, the light lased in the active layer is effectively confined in a stripe-shaped lasing region thereof, and a stable transverse mode of lasing is obtainable.
摘要:
A mounting of semiconductor laser chip on a heat sink or metal mount is improved so as to enable high accuracy of position and direction. A heat sink or metal mount, on which a semiconductor laser chip is mounted, comprises two parts, namely a main mount or larger portion and a sub-mount or smaller portion. The semiconductor laser chip is soldered by a solder layer on the sub-mount utilizing a microscope so as to assure an accurate position and an accurate direction with respect to the sub-mount. Then, the sub-mount is soldered on the main mount by a solder layer with an accurate relation both in position and direction by engaging a linear ridge as a first engaging means provided on the upper face of the main mount with a straight groove and a rear end face as a second engaging means, or by engaging a square recess as a first engaging means and the square bottom of the sub-mount as a second engaging means with each other. As a result of the above-mentioned structure, accurate position and direction of the semiconductor laser chip with respect to the mount is easily obtainable with a high yield.
摘要:
In a semiconductor laser comprising an active layer epitaxially formed on a semiconductor substrate and at least a current limiting layer which defines a current injection region of a stripe shape,the improvement is that said substrate has a terrace part on its principle face,said active layer has two parallel bending parts defining a stripe shape active region facing said current injection region in between andsaid stripe shape active region is disposed with a specified angle to said principle face.
摘要:
In a semiconductor laser which has epitaxial layers including an active layer on a semiconductor substrate, a buffer layer is formed neighboring the active layer, in order to prevent undesirable diffusion of a highly diffusing dopant (Zn) into the active layer from an adjacent layer such as the second clad layer. The buffer layer has the same conductivity as that of the adjacent layer, has a broader energy gap than the active layer, and the dopant of the buffer layer is less diffusing than that of the adjacent layer.
摘要:
On a semiconductor laser substrate, a groove of tapered width is formed, and at least one crystal layer is formed on the substrate. The crystal layer is usable as a waveguide with two light input ends l.sub.1 and l.sub.2 and one light output end l.sub.3 as shown in FIG. 4(C).
摘要:
In a laser comprising a GaAs substrate, an active layer of GaAlAs put between a first and a second clad layers, a buffer layer is disposed between said first clad layer and said substrate, and thermal expansion coefficient of the buffer layer is selected smaller than that of said active layer; thereby an internal stress of the active layer is released and lifetime of the laser is very much prolonged.