| 摘要 |
PURPOSE:To let light emitting part expand or contract in one direction along pn junction face according to the change in applied voltage by making the forbidden band width of a compound semiconductor layer narrower than the forbidden band width of another compound semiconductor and changing the same in one direction along the pn junction face. CONSTITUTION:After an n type AlxGai-xAs layer 12 is formed on an n type GaAs substrate, a p type AlGai-y layer 13 wherein Al composition ratio (y) increases from 0.3 to 0.36 in one parallel direction to the pn junction face is groun. At this time, the Al composition ratio (x) is made, e.g., 0.4, so that the forbindden band width of the layer 12 becomes larger than the forbidded band width of the layer 13. Thereafter, a Zn diffused layer 14, a p side electrode 15 and an n side electrode 16 are formed, after which a pellet is cut out slender in the direction where the Al composition ratio (y) changes through cleaving, mesa etching or other. Since with such constitution the forbidden band width Eg of the layer 13 increases from 1.8eV to 1.9eV as the Al composition ratio (y) increases from 0.3 to 0.36, the light emitting part 17 expands or contracts along the pn junction face with an increase or decrease in applied voltage. |
