Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
34 words
An optical semiconductor device which includes a multiquantum well structure comprising a well layer and a barrier layer, wherein: said well layer is made of InGaAsP; and said barrier layer is made of InGaAlAsP.
Claim 2
Dependent Claim
34 words
An optical semiconductor device which includes a multiquantum well structure comprising a well layer and a barrier layer, wherein: said well layer is made of InGaAsP; and said barrier layer is made of InGaAlAsP.
Claim 3
Dependent Claim
21 words
An optical semiconductor device, according to claim 1, wherein: said well layer has the same As/P ratio as said barrier layer.
Claim 4
Dependent Claim
28 words
An optical semiconductor device, according to claim 2, wherein: said well layer has the same In/Ga ratio as said barrier layer; and said well layer is compressively strained.
Claim 5
Dependent Claim
44 words
An optical semiconductor device, according to claim 2, further comprising guiding layers sandwiching said multiquantum well structure and cladding layers sandwiching said guiding layers, wherein: said well, barrier and guiding layers or said well, barrier, guiding and cladding layers have a same As/P ratio.
Claim 6
Dependent Claim
28 words
An optical semiconductor device, according to claim 1, wherein: said well layer has the same In/Ga ratio as said barrier layer; and said well layer is compressively strained.
Claim 7
Dependent Claim
63 words
An optical semiconductor device, according to claim 5, further comprising an intermediate layer between said well layer and said barrier layer, wherein: said intermediate, well and barrier layers have a same In/Ga ratio and As/P ratio; and said intermediate layer has a Al ratio in III group element contained therein which is a medium value between said barrier layer and said well layer.
Claim 8
Dependent Claim
44 words
An optical semiconductor device, according to claim 6, further comprising guiding layers sandwiching said multiquantum well structure and cladding layers sandwiching said guiding layers, wherein: said well, barrier and guiding layers or said well, barrier, guiding and cladding layers have a same As/P ratio.
Claim 9
Dependent Claim
44 words
An optical semiconductor device, according to claim 5, further comprising guiding layers sandwiching said multiquantum well structure and cladding layers sandwiching said guiding layers, wherein: said well, barrier and guiding layers or said well, barrier, guiding and cladding layers have a same As/P ratio.
Claim 10
Dependent Claim
69 words
An optical semiconductor device which includes a multiquantum well structure comprising a compressive strained well layer and a barrier layer, according to claim 1, wherein: an amount of strain in said well layer is increased, a thickness of said well layer is decreased or a bandgap in said barrier layer is reduced such that a light hole level does not exist in a potential well of said well layer.
Claim 11
Dependent Claim
52 words
An optical semiconductor device which includes a multiquantum well structure comprising a well layer and a barrier layer, wherein: said well layer is made of InGaAs; said barrier layer is made of InGaAlAs; said well layer has the same In/Ga ratio as said barrier layer; and said well layer is compressively strained.
Claim 12
Dependent Claim
52 words
An optical semiconductor device which includes a multiquantum well structure comprising a well layer and a barrier layer, wherein: said well layer is made of InGaAs; said barrier layer is made of InGaAlAs; said well layer has the same In/Ga ratio as said barrier layer; and said well layer is compressively strained.
Claim 13
Dependent Claim
63 words
An optical semiconductor device, according to claim 10, further comprising an intermediate layer between said well layer and said barrier layer, wherein; said intermediate, well and barrier layers have a same In/Ga ratio and As/P ratio; and said intermediate layer has a Al ratio in III group element included therein which is a medium value between said barrier layer and said well layer.
Claim 14
Dependent Claim
52 words
An optical semiconductor device which includes a multiquantum well structure comprising a well layer and a barrier layer, wherein: said well layer is made of InGaP; said barrier layer is made of InGaAlP; said well layer has the same In/Ga ratio as said barrier layer; and said well layer is compressively strained.
Claim 15
Dependent Claim
52 words
An optical semiconductor device which includes a multiquantum well structure comprising a well layer and a barrier layer, wherein: said well layer is made of InGaP; said barrier layer is made of InGaAlP; said well layer has the same In/Ga ratio as said barrier layer; and said well layer is compressively strained.
Claim 16
Dependent Claim
63 words
An optical semiconductor device, according to claim 12, further comprising an intermediate layer between said well layer and said barrier layer, wherein: said intermediate, well and barrier layers have a same In/Ga ratio and As/P ratio; and said intermediate layer has a Al ratio in III group element included therein which is a medium value between said barrier layer and said well layer.
Claim 17
Dependent Claim
86 words
An optical semiconductor device which includes a multiquantum well structure comprising a compressive strained InAsP well layer and a InGaAsP barrier layer, wherein: said well layer has the same As/P ratio as said barrier layer; said well and barrier layers and an InGaAsP intermediate layer have a constant As/P ratio when said InGaAsP intermediate layer is provided between said well and barrier layers; and said intermediate layer has a Ga ratio in III group element contained therein which is less than that of said barrier layer.
Claim 18
Dependent Claim
86 words
An optical semiconductor device which includes a multiquantum well structure comprising a compressive strained InAsP well layer and a InGaAsP barrier layer, wherein: said well layer has the same As/P ratio as said barrier layer; said well and barrier layers and an InGaAsP intermediate layer have a constant As/P ratio when said InGaAsP intermediate layer is provided between said well and barrier layers; and said intermediate layer has a Ga ratio in III group element contained therein which is less than that of said barrier layer.